CONFIDENT CONFIDENTAL DRAFT – AL DRAFT – SUBJECT SUBJECT TO REVISION TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION Exhibit (c)(4) January 15, 2023 Discussion Materials Prepared For The Board Of Directors Of Dagny INTERNAL REFERENCE Galt = DTI Dagny = SDPI CONFIDENTIAL PIPER SANDLER | 1

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION Disclaimer Piper Sandler & Co. ( Piper Sandler or “PSC”) has prepared and provided these materials and any related materials (the Confidential Materials ) solely for the use of the Board of Directors (the Board ) of Dagny (the Company ) in connection with its consideration of the contemplated transaction. Without Piper Sandler's prior written consent, the Confidential Materials may not be circulated or referred to publicly, disclosed to, published, relied upon by any other person, or used or relied upon for any other purpose. Notwithstanding anything herein to the contrary, the Company may disclose to any person the U.S. federal income and state income tax treatment and tax structure of any transaction described herein and all materials of any kind (including tax opinions and other tax analyses) that are provided to the Company relating to such tax treatment and tax structure, without Piper Sandler imposing any limitation of any kind. The Confidential Materials, including this disclaimer, is subject to, and governed by, any written agreement between the Company and Piper Sandler. Piper Sandler engages directly or through its affiliates in various activities, including institutional brokerage and investment and wealth management for individuals and institutions. You understand that this engagement does not prevent Piper Sandler and its affiliates from actively trading the debt and equity securities (or related derivative securities) of third parties, the Company, or other companies which may be the subject of the engagement (for their own account or for the accounts of their customers) or from representing or otherwise providing financial services to third parties, including competitors of the Company. In preparing the Confidential Materials, Piper Sandler has relied upon and assumed, without assuming any responsibility for investigation or independent verification of the accuracy and completeness of all information that is available from public sources as well as all other information supplied to it by, or on behalf of, the Company and/or other sources, including tax, accounting, legal and other information provided to, discussed with or reviewed by Piper Sandler. Piper Sandler is not in any respect responsible for verifying the accuracy or completeness of any such information, conducting any appraisal or valuation of assets or liabilities of any party to the contemplated transaction, or advising or opining on any solvency or viability issues. As such, Piper Sandler does not assume any liability for the accuracy or completeness of such information. These materials are not intended to provide the sole basis for evaluating the contemplated transaction or any other matter, and should be considered by the Board as only one factor in discharging its decision-making duties. PIPER SANDLER | 2

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION Disclaimer (cont’d) Piper Sandler does not provide accounting, tax, legal or regulatory advice. Piper Sandler's role in any due diligence review is limited solely to performing such review as it shall deem necessary to support its own advice and analysis and shall not be on behalf or for the benefit of the Company, or any of its investors, creditors or any transaction counterparty. Forecasts of future results have been provided by the Company to Piper Sandler for use in its analyses. These forecasts are not necessarily indicative of actual future results, which may be significantly more or less favorable than such forecasts, and as such, analyses performed by Piper Sandler based on Company forecasts may not prove to be accurate. Accordingly, Piper Sandler does not assume responsibility for the accuracy or completeness of Company forecasts or the analyses Piper Sandler performs based on these forecasts. The Confidential Materials do not address the underlying business decision of the Company and the Board to engage in the contemplated transaction or any other contemplated transaction, or the relative merits of any strategic alternative referred to herein as compared to any other alternative that may be available to the Company. The Confidential Materials are necessarily based on economic, monetary, market and other conditions as in effect on, and the information made available to Piper Sandler as of, the date of such Confidential Materials and Piper Sandler assumes no responsibility for updating or revising the Confidential Materials. PIPER SANDLER | 3

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION Transaction Overview (Dollar and share amounts in millions, except per share amounts) n In the counterproposal, Galt would acquire all of the outstanding shares of Dagny via tender offer, in which Dagny shareholders would have the option to either exchange for $1.00 worth of Galt shares per Dagny share or receive $1.00 cash per Dagny share l Implies a $27.7 million valuation for Dagny l Analysis assumes floating exchange ratio l Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity Reflects counterproposal exchange ratio. Was 0.243 per Dagny share at time of initial offer letter Dagny Pro Forma Ownership and Implied Equity Consideration Dagny Capitalization At Offer % of Dagny Shares Tendered for Galt Shares At Market At Offer (2) 0% 25% 50% 75% 100% Dagny Diluted Shares Outstanding 32.1 32.1 Cash Offer Price per Share $ 0.76 $ 1.00 Cash Offer Price per Dagny Share $ 1.00 $ 1.00 $ 1.00 $ 1.00 $ 1.00 (1) Implied Dagny Equity Value $ 24.3 $ 3 2.1 Galt Shares per Dagny Share 0.332 0.332 0.332 0.332 0.332 (2) Debt 2.5 2.5 Dagny Fully Diluted Shares Outstanding 32.1 32.1 32.1 32.1 32.1 Less: Cash (4.3) (4.3) Implied Consideration to Dagny Equity Dagny Net Debt (Excl. Tronco) (1.9) (1.9) Galt Shares Issued to Dagny - 2.7 5.3 8.0 10.7 (3 Less: PV of Tronco Note Payments (2.6) (2.6) Galt Share Price (01/09/2024) $ 3.01 $ 3.01 $ 3.01 $ 3.01 $ 3.01 Dagny Net Debt (4.4) (4.4) Stock Consideration $ - $ 8.0 $ 16.1 $ 24.1 $ 32.1 Implied Dagny Enterprise Value $ 19.9 $ 2 7.7 Cash Consideration 32.1 24.1 16.1 8.0 - Total Consideration to Dagny Equity $ 32.1 $ 32.1 $ 32.1 $ 32.1 $ 32.1 Impl. Enterprise Val. (Excl. Tronco) $ 22.5 $ 30.3 Pro Forma Diluted Shares Oustanding Galt Fully Diluted Shares Outstanding 29.8 29.8 29.8 29.8 29.8 Galt Shares Issued to Dagny - 2.7 5.3 8.0 10.7 Total Pro Forma Shares Oustanding 29.8 32.4 35.1 37.8 40.4 Pro Forma Ownership Galt Pro Forma Ownership 100% 92% 85% 79% 74% Dagny Pro Forma Ownership - 8% 15% 21% 26% 1) Calculated using Galt spot share price as of January 9, 2024 and $1.00 offer price per Dagny share 2) Dagny diluted shares includes ~1.7M unvested RSUs that will vest upon change of control PIPER SANDLER | 4 3) Present value of Tronco Note payment schedule provided by management; assumes 30% discount rate Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION Note: Galt Share Price for Exchange Rate Calculation n Galt has calculated exchange rate using Galt’s 20-day VWAP and $1.00 offer price per Dagny Share in initial bid and in presentation to Dagny board n Transaction analysis assumes Galt spot share price as of January 9, 2024 Illustrative Exchange Rates & PF Ownership at Galt Share Prices (1) Galt Share Price Spot Price 20-day VWAP % of Dagny Shares Exchanged for Stock 100% 100% Effective Galt Share Price $ 3.01 $ 3.19 Counterproposal Price per Dagny Share 1.00 1.00 Galt Shares per Dagny Share 0.3322 0.3132 (2) Dagny Fully Diluted Shares Outstanding 32.1 32.1 Galt Shares Issued to Dagny 10.7 10.1 Pro Forma Diluted Shares Oustanding Galt Fully Diluted Shares Outstanding 29.8 29.8 Galt Shares Issued to Dagny 10.7 10.1 Total Pro Forma Shares Oustanding 40.4 39.8 Pro Forma Ownership Galt Pro Forma Ownership 73.6% 74.7% Dagny Pro Forma Ownership 26.4% 25.3% Galt Spot Price is Used in Analysis 1) Galt spot share price as of January 9, 2024; Galt 20-day VWAP calculated as of January 9, 2024 2) Dagny diluted shares includes ~1.7M unvested RSUs that will vest upon change of control PIPER SANDLER | 5 Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION Review of Dagny Management Projection History (1) Prior Management Forecasts vs. Historical Actuals (Dollars in millions) 2018 2019 2020 2021 2022 2023 2024 Actuals Revenue $ 18.2 $ 19.0 $ 10.5 $ 13.3 $ 19.1 Adjusted EBITDA 5.0 4.2 0.1 2.6 5.2 2018 Projections Revenue $ 21.7 Estimate Adj. EBITDA 6.9 Revenue (16%) Miss Adj. EBITDA (28%) 2019 Projections Revenue $ 18.2 Estimate Adj. EBITDA 5.0 Revenue Beat Miss Adj. EBITDA (15%) 2020 Projections Revenue $ 20.4 Estimate Adj. EBITDA 5.3 Revenue (49%) Miss Adj. EBITDA (97%) 2021 Projections Revenue $ 15.1 Estimate Adj. EBITDA 3.3 Revenue (12%) Miss Adj. EBITDA (19%) 2022 Projections Revenue $ 21.5 Estimate Adj. EBITDA 6.3 Revenue (11%) Miss Adj. EBITDA (18%) 2023 Projections - Beg. of Year Revenue $ 26.7 Estimate Adj. EBITDA 7.4 2023/24 Projections - Base Case Revenue $ 20.9 $ 25.7 Estimate Adj. EBITDA 5.9 8.1 1) Source: Company provided information; all projections as of the beginning of each projection year, excluding the 2023/24 base case projection Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity PIPER SANDLER | 6

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION (1) Relative Projected Financial Profiles (2) Gross Profit Growth SG&A as a Percent of Revenue (Indexed to 100 at 2020) (% of revenue) Adj. EBITDA Margin EBITDA Growth (% of revenue) (Indexed to 100 at 2020) 1) Source: Company filings and company provided information 2) Includes EBITDA adjustments PIPER SANDLER | 7 Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION (1) Comparable Companies Analysis (Dollars in millions) Capitalization Enterprise Value To: Market Enterprise EBITDA (2) Equity Value Value 2022 LTM 2023P 2024P Cathedral Energy Services $ 142 $ 225 n/a n/a 3.3x 2.3x DMC Global 322 594 6.5x 5.4x 6.0x 5.7x Forum Energy Technologies 259 351 7.0x 5.9x n/a n/a (2) Hunting 556 614 12.2x 7.8x 6.2x 4.8x (3) KLX Energy Services 177 411 3.8x n/a 2.7x 2.8x NCS Multistage 40 55 3.6x 3.5x 3.8x 4.6x Nine Energy Services 95 402 4.5x 5.1x 6.3x 4.8x Oil States International 391 474 6.7x 5.3x 5.3x 4.7x Phoenix Technology Services 298 326 4.7x 3.4x 2.8x 2.7x Ranger Energy Services 232 255 3.7x 3.0x 2.9x 2.8x Schoeller-Bleckmann 736 727 5.7x 5.4x 4.6x 4.3x Solaris Oilfield Infrastructure 327 366 4.5x 3.7x 3.8x 3.8x Median 4.7x 5.2x 3.8x 4.3x Galt $ 90 $ 86 2.1x 1.6x 1.7x 1.5x Dagny - At Market $ 24 $ 20 4.2x 3.7x 3.4x 2.5x Dagny - At Counterproposal $ 32 $ 28 5.9x 5.2x 4.7x 3.4x Dagny - At Market (Excl. Tronco Note) $ 24 $ 22 4.8x 4.2x 3.8x 2.8x Dagny - At Counterproposal (Excl. Tronco Note) $ 32 $ 30 6.4x 5.6x 5.1x 3.7x 1) Source: Company provided information, public company filings and Capital IQ as of January 9, 2024 2) LTM and balance sheet data as of September 30, 2023; Hunting LTM and balance sheet data as of June 30, 2023 PIPER SANDLER | 8 3) Pro forma for acquisition of Greene's Energy Group, completed March 8, 2023 Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION (1) Contribution Analysis (Dollars in millions) (2) Metric Implied Enterprise Value Contribution Relative Pro Forma Ownership Dagny Galt 20.8% (3) Offer as of 10/2/2023 (4) 23% 77% $88 $336 21% 79% DCF EBITDA 14% 86% 17% 83% 2021 $3 $16 2022 5 41 11% 89% 14% 86% 2023P 6 52 10% 90% 13% 87% 2024P 8 59 12% 88% 15% 85% EBITDA Less Capex 2021 $2 $4 28% 72% 30% 70% 2022 2 17 10% 90% 13% 87% 25% 2023P 2 6 75% 27% 73% 22% 2024P 7 25 78% 25% 75% Asset Metrics ABV (9/30/2022) $8 $56 13% 87% 16% 84% 87% 84% TABV (9/30/2022) 8 56 13% 16% ABV (9/30/2023) 9 81 10% 90% 13% 87% TABV (9/30/2023) 9 81 10% 90% 13% 87% 26.4% (2) Counterproposal 1) Analysis includes the Tronco Note as a cash equivalent in calculating net debt 2) Assumes all Dagny shares are tendered for Galt stock at Galt market price as of January 9, 2024 PIPER SANDLER | 9 3) Assumes all Dagny shares are tendered for Galt shares at the 0.243 Galt shares per Dagny share exchange ratio cited in Galt’s initial bid letter dated October 2, 2023 4) Reflects 5.2x terminal value multiple, 10.6% WACC for Galt and 10.6% WACC for Dagny Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION (1) Implied Exchange Ratios Across Valuation Methodologies (Dollars in millions) Enterprise Equity Exchange Value Value Ratio _. Counterproposal: $ 28 $ 32 0.332x Pro Forma Ownership Splits Dagny Galt Relative Contribution Analysis 0.193x 2021 Adj. EBITDA 17.2% 82.8% 2022 Adj. EBITDA 14.3% 85.7% 0.155x 2023P Adj. EBITDA 13.4% 86.6% 0.144x 2024P Adj. EBITDA 15.1% 84.9% 0.165x 2021 Adj. EBITDA Less Capex 30.0% 70.0% 0.397x 2022 Adj. EBITDA Less Capex 13.0% 87.0% 0.139x 0.351x 2023P Adj. EBITDA Less Capex 27.4% 72.6% 2024P Adj. EBITDA Less Capex 24.7% 75.3% 0.304x (2) 0.243x Relative DCF Anal ysis 20.8% 79.2% Nominal Valuation Outputs Precedent Transactions EV / EBITDA TTM EBITDA (25th Percentile) 4.8x $ 28.2 $ 32.7 0.338x TTM EBITDA (Median) 7.5x 44.1 48.5 0.502x 0.553x TTM EBITDA (75th Percentile) 8.3x 49.0 53.5 (3) Discounted Cash Flow WACC Terminal Mult. 0.748x DCF (Low) 14.0% 4.0x $ 67.9 $ 72.4 DCF (Mid) 10.0% 5.0x 88.0 92.4 0.955x DCF (High) 6.0% 6.0x 114.4 118.8 1.229x 1) Analysis includes the Tronco Note as a cash equivalent in calculating net debt 2) Reflects 5.2x terminal value multiple, 10.6% WACC for Galt and 10.6% WACC for Dagny PIPER SANDLER | 10 3) WACCs shown only used to discount operating cash flows in each case; non-operating cash flows include judgement on the Stabil Drill IP Litigation and payments received on the Tronco Note, which are discounted using rates of 70% and 30%, respectively, across all cases Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION (1) Dagny and Galt Merger Analysis – 2024P (Dollars in millions) 2024P n Adjusted to remove DNR revenue in Galt Dagny Adj. Pro Forma 2024P (Dagny) and COGS (Galt), and for Revenue $ 174.4 $ 25.7 $ (10.9) $ 189.2 estimated depreciation expense Cost of Sales 43.4 9.8 (10.9) 42.4 associated with DNR Capex (Galt) Gross Profit $ 131.0 $ 15.9 $ - $ 146.9 Gross Margin 75% 62% 78% (2) SG&A Expense 72.2 7.8 (3.0) 77.0 n Analysis includes of $3 million base case Adj. EBITDA $ 58.8 $ 8.1 $ 3.0 $ 69.9 Adj. EBITDA Margin 34% 31% 37% cost synergies attributable to Contribution (Excl. Synergies) 88% 12% 100% consolidation of public company costs, (3) D&A Expense 28.0 1.3 (2.8) 26.6 as mentioned in Galt’s proposal Interest Expense, Net 0.0 0.6 - 0.6 (4) Other & EBITDA Adjustments 0.8 1.4 2.2 EBT $ 30.0 $ 4.7 $ 40.5 n Assumes all Dagny shareholders elect to EBT Margin 17% 18% 21% receive stock consideration (5) Income Tax 6.3 1.0 8.5 Net Income $ 23.7 $ 3.7 $ 32.0 (6) Diluted Earnings per Share $ 0.80 $ 0.79 $ Accretion / (Dilution) to Galt (0.00) % Accretion / (Dilution) to Galt (1%) (6) Fully Diluted Shares Outstanding 29.8 10.7 40.4 1) Source: Company provided information, filings and consensus estimates, as appropriate 2) Includes EBITDA adjustments 3) Adjusted to exclude D&A expense associated with 2024 DNR capex spend by Galt. Assumes D&A equal to 2024P capex 4) Other (Net) includes remaining items that were excluded from adjusted EBITDA; For Galt, these include stock option expense, monitoring fees, gain on sale of property, unrealized gain on equity securities, transaction expenses and other expenses; For SDPI, these include impairment of assets, share based compensation, net noncash compensation, gain / loss on disposition of assets and recovery of related party notes receivable 5) Tax rate assumed to be 21% 6) Galt shares issued to Dagny calculated using 0.3322 exchange ratio equal to $1.00 price per Dagny share divided by Galt share price as of January 9, 2024 Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity PIPER SANDLER | 11

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION (1) Floating Value of Stock Offer Since Galt Began Trading (Dollars in millions) (2) VWAP Implied Offer Premium 1-day 32% 10-day 36% 30-day 39% 60-day 37% 1) Source: Capital IQ as of January 9, 2024; Galt began trading on June 21, 2023 following completion of reverse merger 2) Premiums calculated as $1.00 Dagny share price at offer divided by Dagny VWAP PIPER SANDLER | 12 Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION (1) Share Price Ratios Since Galt Began Trading Illustrative Exchange Ratios at Historical Share Prices (2) (3) Illustrative Implied Dagny At-Offer Ownership At Historical Galt Market Prices 1) Source: Capital IQ as of January 9, 2024; Galt began trading on June 21, 2023 following completion of reverse merger 2) $1.00 Dagny share price at offer / Galt spot share price PIPER SANDLER | 13 3) Illustrative historical ownership calculated using current diluted shares outstanding for Dagny and Galt as of January 9, 2024 Note: Analysis excludes transaction fees and expenses that are expected to be absorbed by the merged entity

CONFIDENTAL DRAFT – SUBJECT TO REVISION CONFIDENTIAL DRAFT – SUBJECT TO REVISION For information on Piper Sandler locations, visit PiperSandler.com. ® Piper Sandler Companies (NYSE: PIPR) is a leading investment bank driven to help clients Realize the Power of Partnership . Securities brokerage and investment banking services are offered in the U.S. through Piper Sandler & Co., member SIPC and NYSE; in the U.K. through Piper Sandler Ltd., authorized and regulated by the U.K. Financial Conduct Authority; and in Hong Kong through Piper Sandler Hong Kong Ltd., authorized and regulated by the Securities and Futures Commission Alternative asset management and fixed income advisory services are offered through separately registered advisory affiliates. ©2024. Since 1895. Piper Sandler Companies. 800 Nicollet Mall, Minneapolis, Minnesota 55402-7036 PIPER SANDLER | 14