Our chrome TRV heads are manufactured to the highest quality and their durable design allow them to combat the test of time. Our further 1 year warranty ensures peace of mind. These TRV heads are for both Domestic and Commercial use and will fit all manufactures valves with M30 x 1.5 threads (Normal Industry Standard). The heads can also be fitted both Horizontally and Vertically. More control: Our TRV valves have built-in frost protection and offer you room temperature control between 7 and 29 °C. Technical information: Thread size M30 x 1.5, frost protection, adjustable temperature.