Product Warranty

9 Months Ended

Sep. 30, 2016

Product Warranties Disclosures [Abstract]

Product Warranty

Product Warranty

As of September 30, 2016, and December 31, 2015, MRV's product warranty liabilities recorded in accrued liabilities were $0.5 million and $0.6 million, respectively. MRV accrues for warranty costs as part of cost of sales based on associated material product costs, technical support labor costs and associated overhead. The products sold are generally covered by a warranty for periods of 90 days to three years.

The following table summarizes the activity related to the product warranty liability during the nine months endedSeptember 30, 2016 (in thousands):

Balance at beginning of the period	$	593
Cost of warranty claims	(73		)
Accruals for product warranties	29
Balance at end of the period	$	549