Concentrations and credit risk

12 Months Ended

Mar. 31, 2018

Accounting Policies [Abstract]

Concentrations and credit risk

16 Concentrations and credit risk

The Company operates principally in the PRC (including Hong Kong) and grants credit to its customers in this geographic region.  Although the PRC is economically stable, it is always possible that unanticipated events in foreign countries could disrupt the Company’s operations.

Financial instruments that potentially subject the Company to a concentration of credit risk consist of cash and trade  receivables.  The Company does not require collateral to support financial instruments that are subject to credit risk.

At March 31, 2017 and 2018, the Company had credit risk exposure of uninsured cash and deposits with maturities of less than one year in banks of approximately $3,745,000 and $8,751,000, respectively.

A substantial portion, 56%, 45% and 31% of revenue, was generated from one customer for the years ended March 31, 2016, 2017 and 2018, respectively.

The net sales to customers representing at least 10% of net total sales are as follows:

	Year Ended March 31,
	2016				2017				2018
	$ in thousands		%		$ in thousands		%		$ in thousands		%
Customer A		3,874		15		2,729		14		3,579		31
Customer B		1,738		7		1,563		8		1,662		14
Customer C		1,969		8		2,435		13		1,599		14
Customer D *		14,145		56		8,472		45		1,115		10
		21,726		86		15,199		80		7,955		69

* That customer has stopped purchasing from us as of June 2017.

The following customers had balances of at least 10% of the total trade receivables at the respective balance sheet dates set forth below:

	March 31,
	2017				2018
	$ in thousands		%		$ in thousands		%
Customer A		328		28		234		30
Customer C		455		39		200		25
Customer E		-		-		113		14
Customer B		162		14		-		-
				81				69

At March 31, 2017 and 2018, these customers accounted for 81% and 69%, respectively, of net trade receivables.  The trade receivables have repayment terms of not more than twelve months.