STOCKHOLDERS' EQUITY AND STOCK-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 30, 2019

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]



	Shares		Weighted Average Grant Fair Value
Balance, December 29, 2018	2,213,249		$	2.51
Granted	70,000		1.26
Forfeited	(122,375	)	3.06
Vested	(10,000	)	2.90
Balance, March 30, 2019	2,150,874		$	2.44

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions

The value of restricted stock grants that vest based on market conditions is computed on the date of grant using the Monte Carlo model with the following assumptions:



	For the three months ended March 30, 2019
Performance price target	$	5.25		$	6.00		$	7.00
Expected volatility	48.3		%	48.3		%	48.3		%
Interest rate	1.97		%	1.97		%	1.97		%
Expected life (years)	3			3			3
Dividend yield	—		%	—		%	—		%

Stock-Based Compensation Expense

The following table summarizes stock-based compensation expense within each of the categories below as it relates to non-vested restricted common stock awards for the three months ended March 30, 2019 and March 31, 2018 (no tax benefits were recognized):



	Three Months Ended
	March 30, 2019		March 31, 2018
Cost of product revenues	$	32,108	$	110,226
Research and development	104,730		274,316
Selling, general and administrative	679,004		1,014,873
Total	$	815,842	$	1,399,415

Unr