Condensed Consolidated Statements of Operations (Unaudited) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Revenue
Products sales and leasing	$ 9,614,336	$ 9,784,308	$ 24,998,000	$ 23,173,987
Shipping and installation revenue	1,383,289	2,077,943	5,320,792	5,572,877
Royalties	483,179	533,750	1,387,307	1,344,240
Total revenue	11,480,804	12,396,001	31,706,099	30,091,104
Cost of goods sold	8,243,291	8,273,621	22,275,067	22,621,805
Gross profit	3,237,513	4,122,380	9,431,032	7,469,299
Operating expenses
General and administrative expenses	1,442,722	966,702	3,925,456	2,698,129
Selling expenses	564,453	501,269	1,825,303	1,629,771
Total operating expenses	2,007,175	1,467,971	5,750,759	4,327,900
Operating income (loss)	1,230,338	2,654,409	3,680,273	3,141,399
Interest income (expense)
Interest expense	(43,501)	(50,126)	(134,640)	(111,675)
Interest income	9,047	0	27,935	28,205
Gain on sale of assets	15,499	7,254	32,017	21,297
Other income	10,871	33,770	34,522	51,229
Total other expense	(8,084)	(9,102)	(40,166)	(10,944)
Income before income tax expense	1,222,254	2,645,307	3,640,107	3,130,455
Income tax expense (benefit)	474,000	954,000	1,323,000	1,110,000
Net income (loss)	$ 748,254	$ 1,691,307	$ 2,317,107	$ 2,020,455
Basic and diluted earnings per share (in dollars per share)	$ 0.15	$ 0.34
Weighted average number of common shares outstanding:
Basic (in shares)	5,054,148	4,924,366	5,036,102	4,924,366
Diluted (in shares)	5,099,387	4,964,965	5,075,199	4,958,473
Basic income (loss) per share (in dollars per share)			$ 0.46	$ 0.41