With fine machine threads for attachment to wall hydrant. Nickel plated-for use on 485BFP & 486BFP frost proof wall hydrants The VPC PK1390 is a replacement self-draining vacuum breaker for frost free hydrants with FINE THREADS (will not connect to hose threaded faucet). A must on all outdoor systems. It can easily be adapted with new installs or existing systems. ? Red brass construction, nickel plated for protection from extreme weather ? Drains water from faucet upon shut off ? For replacing leaking vacuum breakers on fine threaded hose-bibs and sillcocks ? Red brass with 80-83% copper content ? For outdoor use; not for potable water ? ASSE 1019 approved; IAMPO certified