INVENTORIES, NET - Schedule of inventories (Details) ¥ in Thousands, $ in Thousands	Dec. 31, 2024 CNY (¥)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 CNY (¥)	Dec. 31, 2022 CNY (¥)
INVENTORIES, NET
Finished goods	¥ 80,853		¥ 105,542
Raw materials	31,472		51,761
Inventories, net	112,325	$ 15,388	157,303
Inventory written down	¥ 3,104		¥ 13,182	¥ 3,820

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- Definition

Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer.

+ References

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- Definition

Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 852
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Amount before valuation and LIFO reserves of raw materials expected to be sold, or consumed within one year or operating cycle, if longer.

+ References

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Amount of accumulated impairment for inventory.

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