Tank neck thread is M18 x 1,5 ISO. Nautec S-valves are standard shut off devices in accordance with DIN EN 12209-2 (G 5/8″), for an operating pressure of 232 bar with vertically arranged shut-off mechanism and outlet. Only 1 first stage can be connected.Equipped with “Full-Metal-Core-Rubber Knobs” (for maximum grip).The valve is 100 % oxygen-compatible and lead free.