CONDENSED STATEMENTS OF OPERATIONS - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Aug. 28, 2021	Aug. 29, 2020	Aug. 28, 2021	Aug. 29, 2020
Income Statement [Abstract]
NET SALES	$ 8,180	$ 4,926	$ 19,865	$ 16,760
COST AND EXPENSES:
Cost of goods sold	(4,407)	(3,115)	(11,237)	(9,982)
Research and development	(510)	(306)	(1,253)	(1,192)
Selling, general and administrative expenses	(1,649)	(1,342)	(4,628)	(4,076)
Total cost and expenses	(6,566)	(4,763)	(17,118)	(15,250)
OPERATING INCOME	1,614	163	2,747	1,510
Other income (loss), net	(210)	1	(190)	27
INCOME BEFORE TAXES	1,404	164	2,557	1,537
Provision for taxes	316	35	477	227
NET INCOME	$ 1,088	$ 129	$ 2,080	$ 1,310
NET INCOME PER SHARE, BASIC AND DILUTED	$ 0.42	$ 0.05	$ 0.81	$ 0.51
DIVIDENDS PER SHARE	$ 0	$ 0	$ 0.10	$ 0.10
WEIGHTED AVERAGE OF SHARES, basic and diluted	2,578,315	2,578,315	2,578,315	2,578,315