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16. REVENUES (Details Narrative) - USD ($) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2019 | Dec. 31, 2018
Deferred revenue | $ 93,609 | $ 835,785
Deferred revenue recorded in prior year | 765,609 |
Product Deposits [Member] |  |
Deferred revenue | 35,520 | 791,913
Maintenance Fees [Member] |  |
Deferred revenue | $ 58,089 | $ 43,872

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