This is a tough Fibre-Composite Shatter proof Adaptor, not cheap brittle plastic like others. TRV/Thermostat Radiator ValveADAPTOR FOR OLDER 28mm Ring-Screw Models with1mm Thread Pitch ONLY. Suitable for older, pre 1999 radiator Valves with the now Obsolete 28mm Ring-Screw fixing, and this then Converts it to the Modern 2025 Standard 30mm/M30 Ring-Screw fitting.
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