Condensed Consolidated Balance Sheets (Current Period Unaudited) (Parentheticals) - USD ($)	Jun. 30, 2023	Dec. 31, 2022
Accounts receivable, allowance for doubtful accounts	$ 50,230	$ 59,559
Inventories, allowance for excess and obsolete inventory	732,638	663,227
Property and equipment, accumulated depreciation	10,374,274	9,046,499
Intangible assets, accumulated depreciations	$ 497,445	$ 438,250
Preferred stock, par value (in dollars per share)	$ 0.001	$ 0.001
Preferred stock, shares authorized (in shares)	2,500,000	2,500,000
Preferred stock, shares issued (in shares)	0	0
Preferred stock, shared outstanding (in shares)	0	0
Common stock, par value (in dollars per share)	$ 0.001	$ 0.001
Common stock, authorized (in shares)	12,500,000	12,500,000
Common stock, issued (in shares)	5,700,226	5,498,260
Common stock, outstanding (in shares)	5,700,226	5,498,260