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1. A backflow prevention device, the backflow prevention device comprising:
a housing defining a water flow stream; an upstream shutoff valve, wherein the upstream shutoff valve is configured to allow a user to control the water flow stream through the housing; an upstream check valve:
located within the housing downstream of the upstream shutoff valve; andincluding:
an orifice, wherein the orifice is configured to allow the water flow stream through the upstream check valve; anda clapper, wherein the clapper is configured to:
allow the water flow stream through the orifice when open; andprevent the water flow stream through the orifice when in a closed position by mating with the orifice; a downstream check valve:
located within the housing downstream of the upstream check valve; andincluding:
an orifice, wherein the orifice is configured to allow the water flow stream through the downstream check valve;a clapper, wherein the clapper is configured to:
allow the water flow stream through the orifice when open; andprevent the water flow stream through the orifice when in a closed position by mating with the orifice; a downstream shutoff valve, wherein the downstream shutoff valve is configured to allow a user to control the water flow stream through the housing; an access port in the housing configured to provide a user with access to the upstream check valve and the downstream check valve; a cover:
configured to cover the entirety of the access port; andincluding a portion of a lateral surface of a right cylinder; andwherein the lateral surface is non-concentric with the axis of curvature of the housing at the access port; and a seal configured to sealingly engage the cover and the housing along the perimeter of the cover.
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