(12) CONCENTRATIONS

The Company sourced approximately 42% of components for its electrotherapy products from one vendor during the years ended December 31, 2016 and 2015, respectively. Management believes that its relationships with suppliers are good; however, the Company has delayed and extended payments to many of its vendors for cash flow reasons, which has caused many of its vendors to require pre-payment for products or services. If the relationships were to be replaced, there may be a short-term disruption to operations, a period of time in which products may not be available and additional expenses may be incurred.

The Company had gross receivables from a private health insurance carrier at December 31, 2016 and 2015 that made up approximately 10% and 5%, respectively, of the net accounts receivable balance.