Bristan Thermostatic Cartridge (replacement for old brass version) 00622415 : Amazon.co.uk: DIY & Tools
Bristan Cardinal Thermostatic antique shower valve shower spares and parts | Bristan Cardinal | National Shower Spares
Bristan 1901 thermostatic exposed single control shower valve with rigid riser kit shower spares and parts | Bristan N2 SQSHXDIV C | National Shower Spares