4.  Customer Concentrations and Accounts Receivable

Cal Microturbine, one of the Company’s domestic distributors, and Supernova Energy Services, one of the Company’s Latin American distributors, accounted for 24% and 12% of revenue for the three months ended December 31, 2020, respectively. Optimal Group Australia Pty Ltd, one of the Company’s Australian distributors, accounted for 11% of revenue for the three months ended December 31, 2019. Cal Microturbine accounted for 16% of revenue  for the nine months ended December 31, 2020. E-Finity accounted for 12% of revenue for the nine months ended December 31, 2019.

Additionally, Cal Microturbine and E-Finity, accounted for 18% and 14% of net accounts receivable as of December 31, 2020 and March 31, 2020, respectively. The Company recorded a net bad debt recovery of approximately $0.2 million during the three and nine months ended December 31, 2020 and $0.1 million during the three and nine months ended December 31, 2019.