Condensed Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Current Assets:
Cash and cash equivalents	$ 2,386	$ 13,250
Marketable securities	16,261	3,803
Accounts receivable, net of allowances of $38 and $35, respectively	4,105	3,393
Inventories, net	4,417	3,875
Prepaid expenses and other current assets	285	229
Total Current Assets	27,454	24,550
Property, plant and equipment:
Land	536	536
Buildings and improvements	3,973	3,973
Machinery and equipment	16,977	16,974
Gross property, plant and equipment	21,486	21,483
Less: accumulated depreciation	(19,390)	(19,304)
Net property, plant, and equipment	2,096	2,179
Intangible assets, net	496	552
Deferred income taxes, net	145	173
Other assets, net		101
Total Assets	30,191	27,555
Current Liabilities:
Accounts payable	1,369	1,477
Accrued compensation and commissions	1,441	872
Other accrued expenses	365	278
Total Current Liabilities	3,175	2,627
Commitments and Contingencies (Note M)
Stockholders’ Equity
Common stock, $0.01 par value - 10,000,000 shares authorized; 4,906,246 shares issued and 4,824,662 shares outstanding at September 30, 2018, and 4,774,477 shares issued and 4,692,893 shares outstanding at December 31, 2017	49	47
Additional paid-in capital	40,978	40,035
Accumulated deficit	(13,431)	(14,609)
Treasury stock, 81,584 shares held in treasury at cost at September 30, 2018 and December 31, 2017	(580)	(580)
Accumulated other comprehensive income		35
Total Stockholders' Equity	27,016	24,928
Total Liabilities and Stockholders' Equity	$ 30,191	$ 27,555