The Caleffi H83V7U is a genuine replacement cartridge kit designed for Caleffi straight or angle radiator valves and lockshield valves. This comprehensive kit includes one cartridge for a straight or angle radiator valve, one cartridge for a straight or angle lockshield valve, and a hex key for easy installation. It is suitable for use with water and glycol solutions (up to 30% glycol) in heating systems. The kit is compatible with valves featuring 1/2"M and 3/4"M connections, such as the Caleffi 387201 straight radiator valve. It operates effectively up to a maximum working pressure of 10 bar and a maximum differential pressure of 1 bar, with a maximum working temperature of 100 °C.