Exceeding BS6752 & ISO 7171 this gauge is of the safest possible design. Tamper proof high flow safety valve. Captive pressure adjusting knob. Compatible with all gases. Cone inlet filter designed to prevent ingress of foreign particles into the regulator. Unperforated diaphragm reducing the possibility of leaks, improving safety. SPECIFICATION: Output pressure:3.5bar / 50 psi.