The Connector (CN, CR) valve is a check valve with a pipe nipple or connector housing. It is designed to be used in installations where a check valve with male pipe threads are required. The CN valve is adaptable for use as a check valve, vacuum breaker, or low pressure relief valve. Two valves used in combination make an excellent pressure vacuum vent. NPT threads are per ASME B1.20.1. This valve is also available with ISO 7 "R" threads (CR).
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