The Toyotomi 20476474 is a genuine Washer B1 for BS-36UFF, OM-148. Genuine washer used at the insulator on these water heaters.
This is an OEM Toyotomi part, so it fits and performs the way the original did. Confirm your heater model before ordering; the model is on the rating label on the unit. If you are not sure which part you need, Rural Energy support can check it against your model and serial number.
Rural Energy is a Toyotomi distributor and keeps Oil Miser water heater parts in stock for fast shipping to dealers and homeowners.