CONDENSED CONSOLIDATED BALANCE SHEETS - USD ($)	Jun. 30, 2024	Dec. 31, 2023
Current assets:
Cash and cash equivalents	$ 560,500	$ 796,100
Investment securities	3,295,100	4,928,700
Trade accounts receivable, less allowance for doubtful accounts of $33,600 at June 30, 2024 and December 31, 2023	1,214,900	1,157,100
Inventories	4,797,700	4,883,900
Income tax receivable	73,600	161,400
Prepaid expenses and other current assets	444,600	413,500
Total current assets	10,386,400	12,340,700
Property and equipment, net	999,800	1,082,300
Goodwill	115,300	115,300
Other intangible assets, net	1,006,000	1,249,900
Inventories	598,300	609,000
Operating lease right-of-use assets	1,109,800	1,273,900
Other assets	59,400	59,400
Total assets	14,275,000	16,730,500
Current liabilities:
Accounts payable	712,600	711,700
Accrued expenses	685,900	777,900
Contract liabilities	28,700	23,600
Lease liabilities, current portion	346,800	324,100
Total current liabilities	1,774,000	1,837,300
Lease liabilities, less current portion	819,400	1,007,800
Total liabilities	2,593,400	2,845,100
Shareholders' equity:
Common stock, $0.05 par value; 30,000,000 shares authorized; 10,503,599 and 10,145,211, shares issued and 10,503,599 and 10,145,211, shares outstanding at June 30, 2024 and December 31, 2023	525,200	507,300
Additional paid-in capital	42,002,600	40,844,600
Accumulated other comprehensive gain (loss)	(25,900)	18,600
Accumulated deficit	(30,820,300)	(27,485,100)
Total shareholders' equity	11,681,600	13,885,400
Total liabilities and shareholders' equity	$ 14,275,000	$ 16,730,500