Ideal Standard Shower outlet flow regulator 9 litres per minute
Shower and tap tail water saving flow regulator – Freeflush Water Management Ltd.
Ecostar Shower Regulator | Homebase
Shower Flow Control Valve, APLusee Brass Water Pressure Regulator with On Off Adjustable Switch Lever for Universal Shower Head and Arm, Chrome : Amazon.co.uk: DIY & Tools
Shower Flow Reducer Limiter Set - Up to 70% Water Saving 4 L/min : Amazon.co.uk: DIY & Tools
Flow Restrictors-Regulators-Limiters - KOBOLD USA
Shower Head Flow Controls - add a trickle feature to your shower!
Shower Flow Restrictor, Water Saving Shower Head - Renergise
YPLonon Shower Flow Reducer Limiter Set 5PCS Shower Restrictors with G1/2 Adapters 80% Water Saving Shower Head Flow Regulator Valves for Home and Hotel Bathroom - 5 Different Flows : Amazon.co.uk: DIY