4. Customer Concentrations and Accounts Receivable

Accounts receivables are presented on the Condensed Consolidated Balance Sheets, net of estimated credit losses. The Company applies the aging method by pooling receivables based on levels of delinquency and applying historical loss rates on what has been historically uncollectible by aging categories. The historical loss rate is adjusted for current conditions and reasonable and supportable forecasts of future losses, as necessary. Additionally, the allowance for credit loss calculation includes subjective adjustments for qualitative risk factors that could likely cause estimated credit losses to differ from historical experience. The factors include assessments of various economic conditions, significant events that have or will occur, geographic location, size and credit ratings of the customers. The Company may also record a specific reserve for individual accounts when the Company becomes aware of specific customer circumstances, such as in the case of a bankruptcy filing or deterioration in the customer’s operating results or financial position. Accounts deemed uncollectible are written off against the allowance for credit loss.

Changes in the current expected credit losses (“CECL”) allowance for accounts receivable are as follows (in thousands):

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Sales to DTC Soluciones (“DTC”), one of the Company’s distributors, accounted for 27% of revenue for the three months ended December 31, 2025. Sales to E-Finity Distributed Generation (“E-Finity”), Lone Star Power Solutions, LLC (“Lone Star”) and Cal Microturbine, LLC (“Cal Microturbine”), three of the Company’s distributors, accounted for 15%, 14% and 11% of revenue for the three months ended December 31, 2024, respectively.  Sales to Cal Microturbine, E-Finity, DTC and Lone Star, four of the Company’s distributors, accounted for 20%, 17%, 12% and 10% of revenue for the nine months ended December 31, 2025, respectively. On August 13, 2025, the Company completed its acquisition of Cal Microturbine. Refer to Note 20— Business Combination for further details. E-Finity and Lone Star, two of the Company’s distributors, accounted for 16% and 13% of revenue for the nine months ended December 31, 2024, respectively.

Additionally, Supernova Energy Services SAS and RSP Systems, two of the Company’s distributors, accounted for 16% and 11% of accounts receivable as of December 31, 2025, respectively. Lone Star and Optimal Group Australia accounted for 18% and 10% of accounts receivable as of March 31, 2025, respectively. The Company recorded a credit loss expense of zero and $0.2 million during the three months ended December 31, 2025 and 2024, respectively. The Company recorded a credit loss expense of $0.4 million and $0.6 million during the nine months ended December 31, 2025 and 2024, respectively.