Annual report pursuant to Section 13 and 15(d)

Product warranty

v3.20.4
Product warranty
 12 Months Ended
Dec. 31, 2020
Guarantees [Abstract]  
Product warranty Product warranty
We reserve an estimate of our exposure to warranty claims based on both current and historical product sales data and warranty costs incurred. The majority of our products are sold with a one-year warranty. We assesses the adequacy of our recorded warranty liability periodically and adjust the reserve as necessary. The warranty liability is included in accrued expenses on the accompanying consolidated balance sheets.
Changes in our warranty reserve were as follows:
Warranty reserve, December 31, 2018 $ 140,600 
Warranty provision for units sold 535,700 
Costs of warranty incurred (471,000)
Warranty reserve, December 31, 2019 205,300 
Warranty provision for units sold 185,696 
Costs of warranty incurred (226,196)
Warranty reserve, December 31, 2020 $ 164,800