This product simply converts a 15mm compression fitting to 10mm Push-Fit. When making 10mm Push-Fit TRVs all the major manufactuers simply put a 15mm TRV together with a 10mm Push-Fit elbow. Usual..

Pegler Terrier III TRV Head Direct replacement for Terrier II head (part number 850685 picture below). Also suitable for all Regis and Bulldog TRVs  ..

Replacement TRV head for Belmont TRVs..