Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Current assets:
Cash and cash equivalents	$ 6,381	$ 4,676
Trade accounts receivable, net	5,778	3,964
Inventories, net	8,426	13,513
Prepaid expenses and other current assets	1,455	1,733
Total current assets	22,040	23,886
Property, plant and equipment, net	3,701	3,964
Right-of-use (ROU) asset	3,013	2,885
Investment in securities	1,838	2,635
Deferred tax assets, net	4,272	4,373
Other assets	122	197
Total assets	34,986	37,940
Current liabilities:
Accounts payable	3,129	5,310
Accrued compensation and related taxes	1,428	1,271
Accrued warranty expense	911	1,248
Accrued other expenses and other current liabilities	660	479
Dividends payable	250	252
Short-term lease liability	496	369
Note payable-current portion	81	78
Deferred revenue	667	369
Total current liabilities	7,622	9,376
Note payable, net of current portion	268	328
Long-term lease liability	2,829	2,606
Deferred revenue	2,622	2,354
Total liabilities	13,341	14,664
Commitments and contingencies
Stockholders' equity:
Preferred stock; $1.00 par value; 1,000,000 authorized shares; none issued or outstanding	0	0
Common stock; $.60 par value; 20,000,000 authorized shares; 13,962,366 and 13,929,381 issued and 12,511,966 and 12,596,923 outstanding shares at September 30, 2020 and December 31, 2019, respectively	8,377	8,357
Additional paid-in capital	26,281	26,095
Accumulated deficit	(7,611)	(6,043)
Treasury stock, at cost, 1,450,400 and 1,332,458 shares at September 30, 2020 and December 31, 2019, respectively	(5,402)	(5,133)
Total stockholders' equity	21,645	23,276
Total liabilities and stockholders' equity	$ 34,986	$ 37,940