4.  Customer Concentrations and Accounts Receivable

Sales to E-Finity Distributed Generation, LLC (“E-Finity”) and Cal Microturbine (“CAL”), two of the Company’s domestic distributors, each accounted for 12% of revenue for the three months ended June 30, 2020. Sales to E-Finity and CAL accounted for 12% and 10%, respectively, of revenue for the three months ended June 30, 2019.

Additionally, E-Finity accounted for 13% of net accounts receivable as of June 30, 2020. Innovative Energy Company Limited, one of the Company’s Jamaican distributors, and DTC Soluciones S.A. de C.V. (“DTC”), one of the Company’s Mexican distributors, accounted for 12% and 11%, respectively, of net accounts receivable as of June 30, 2019.