4. Inventories

12 Months Ended

Mar. 31, 2019

Inventory Disclosure [Abstract]

Inventory Disclosure [Text Block]

4.                   Inventories

Inventories consist of:

	March 31,
	2019			2018
Purchased parts	$	2,709,235		$	3,571,874
Work-in-process		721,397			1,051,725
Finished goods		-			66,335
Less: Allowance for obsolete inventory		(498,000	)		(420,000	)
	$	2,932,632		$	4,269,934

Work-in-process inventory includes $673,437 and $956,349 for government contracts at March 31, 2019 and 2018, respectively.