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NOTE 5—INVENTORIES

Inventories, which are comprised of chemicals and raw materials available for resale and parts and consumables used in operations, are valued at the lower of cost and net realizable value, with cost determined under the weighted-average method. The significant components of inventory are as follows:

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During the Current Quarter and Current Period, the Company recorded net charges to the reserve for excess and obsolete inventory of less than $0.1 million. During the Prior Quarter and Prior Period, the Company recorded net credits to the reserve for excess and obsolete inventory of $0.4 million. Net charges and credits to the reserve for excess and obsolete inventory were recognized within cost of revenue on the accompanying consolidated statements of operations. The Company’s inventory reserve was $4.9 million and $4.8 million as of June 30, 2025 and December 31, 2024, respectively. The reserve for excess and obsolete inventories is determined based on the Company’s historical usage of inventory on hand, as well as future expectations and the amount necessary to reduce the cost of the inventory to its estimated net realizable value.