ACCOUNTS RECEIVABLE AND CUSTOMER DEPOSITS - Accounts receivable (Details) - USD ($)	Dec. 31, 2019	Dec. 31, 2018
ACCOUNTS RECEIVABLE AND CUSTOMER DEPOSITS
Accounts receivable	$ 196,204	$ 125,622
Less: Allowance for doubtful accounts	(111,000)	(9,000)
Total	$ 85,204	$ 116,622