INCOME TAXES - Deferred tax assets and liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Sep. 30, 2018
Deferred tax assets:
Inventory	$ 102	$ 101
Accrued compensation and vacation	162	68
Accrued expenses and other	379	277
Domestic net operating loss carryforwards	3,282	3,328
Basic difference for intangible assets	254	114
Stock compensation expense	2	5
AMT credit carryover	31	62
Total deferred tax assets	4,212	3,955
Deferred tax liabilities:
Prepaid expenses	(121)	(60)
Basis difference for fixed assets	(219)	(280)
Total deferred tax liabilities	(340)	(340)
Total net deferred tax assets	3,872	3,615
Valuation allowance for net deferred tax assets	(3,841)	(3,553)
Net deferred tax asset	$ 31	$ 62