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Summary of Significant Accounting Policies - Warranty Accrual (Details) - USD ($)
6 Months Ended
Apr. 30, 2020
Apr. 30, 2019
Accounting Policies [Abstract]    
Beginning balance $ 60,000 $ 80,000
Warranty service provided (71,803) (59,243)
New product warranties 27,101 38,587
Changes to pre-existing warranty accruals 34,702 10,656
Ending balance $ 50,000 $ 70,000