SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Concentration risks (Details)	3 Months Ended	6 Months Ended
Jun. 30, 2023 USD ($) customer	Jun. 30, 2022 USD ($) customer	Jun. 30, 2023 USD ($) customer	Jun. 30, 2022 USD ($) customer
Concentration risks
Sales, net	$ 7,971,280	$ 14,336,569	$ 18,972,382	$ 59,078,919
Increase in allowance for doubtful accounts			$ 370,573
Net Sales \| Customer Concentration Risk
Concentration risks
Number of significant customers \| customer	3	3	3	4
Sales, net	$ 4,400,000	$ 8,300,000	$ 10,200,000	$ 44,400,000
Net Sales \| Customer Concentration Risk \| Significant customers
Concentration risks
Concentration risk, percentage of total products purchased	55.00%	57.60%	53.90%	75.20%
Cost of Sales, Manufacturing \| Supplier Concentration Risk \| China
Concentration risks
Concentration risk, percentage of total products purchased	84.00%	84.00%	89.00%	91.00%

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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