England Rugby RFU Thermoreg Bonded Fleece 1/4 Zip Top 17/18 – Graphite Being at the right temperature when training is extremely important. Our ThermoReg tech helps achieve a consistent temperature allowing you to concentrate on what matters. It is is the small margins that make players and teams great. 100% Polyester ThermoReg Technology creates an insulating layer that retains warmth while avoiding heat build-up in key areas. Allowing your body to regulate it’s temperature.