4. Inventory, net (Details) - USD ($) |
Mar. 31, 2021 |
Dec. 31, 2020 |
Dec. 31, 2019 |
|---|---|---|---|
| Inventory Disclosure [Abstract] | |||
| Parts | $ 40,180 | $ 45,509 | $ 31,458 |
| Finished goods | 51,903 | 67,549 | 102,889 |
| Total | 92,083 | 113,058 | 134,347 |
| Less inventory reserve | (67,275) | (70,562) | (71,414) |
| Inventory, net | $ 24,808 | $ 42,496 | $ 62,933 |
| X | ||||||||||
- References No definition available.
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| X | ||||||||||
- Definition Amount before valuation and LIFO reserves of completed merchandise or goods expected to be sold within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Gross amount, as of the balance sheet date, of merchandise, goods, commodities, or supplies held for future sale or to be used in manufacturing, servicing or production process. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount by which inventory stated at last-in first-out (LIFO) is less than (in excess of) inventory stated at other inventory cost methods. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Amount after valuation and LIFO reserves of inventory expected to be sold, or consumed within one year or operating cycle, if longer. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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| X | ||||||||||
- Definition Gross amount of unprocessed materials to be used in manufacturing or production process and supplies that will be consumed. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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