Inventories (in thousands):

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Note receivable:

On June 13, 2024, the Company entered into a Senior Secured Promissory Note and Security Agreement (“Promissory Note and Security Agreement”) with an unaffiliated third-party company (“the Borrower”). Pursuant to the Promissory Note and Security Agreement, the Company agreed to provide the Borrower with a term loan in the principal amount of $150,000 (“June 2024 Note”). The June 2024 Note matures on October 11, 2024. Borrowings under the June 2024 Note bear interest at a rate per annum equal to 5.12%. On the maturity date, subject to any extension, the Borrower will be obligated to make a payment equal to all unpaid principal and accrued interest. Note receivable is included in other assets on the condensed consolidated balance sheets. There was no note receivable at December 31, 2023.

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3.Balance Sheet Components, continued

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Property and equipment, net (in thousands):

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Depreciation and amortization expense for the three months ended June 30, 2024 and 2023 were approximately of $28,000 and $32,000, respectively. Depreciation and amortization expense for the six months ended June 30, 2024 and 2023 were approximately  $48,000 and $65,000, respectively.

Accrued liabilities (in thousands):

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