CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($)	6 Months Ended
Mar. 31, 2020	Mar. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 766,013	$ 341,920
Adjustments to reconcile net income to net cash (used in) provided by operating activities:
Depreciation and amortization	205,154	234,846
Share-based compensation expense:
Stock awards	159,992	203,386
Deferred income taxes	38	33
(Increase) decrease in:
Accounts receivable	(336,444)	829,445
Contract asset	(106,666)
Inventories	(350,368)	(290,704)
Prepaid expenses and other current assets	(105,615)	(19,134)
Income taxes receivable/payable	(311,896)	7,305
Increase (decrease) in:
Accounts payable	276,682	(543,857)
Accrued expenses	(13,990)	(9,660)
Contract liability	67,905	169,098
Net cash provided by operating activities	250,805	922,678
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of property and equipment	(32,420)	(72,195)
Net cash used in investing activities	(32,420)	(72,195)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from exercise of stock options	8,822
Net cash provided by financing activities	8,822
Net increase in cash and cash equivalents	227,207	850,483
Cash and cash equivalents, beginning of year	22,416,830	20,390,713
Cash and cash equivalents, end of period	22,644,037	$ 21,241,196
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION
Cash paid for income tax	$ 2,456

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