The PVMK is a quick acting, in-line or right-angled lever operated valve. The lever, connected to a self-lubricating plastic cam-piston, actuates the valve stem and valve plate through PTFE bearings. The valve plate ‘O’ ring groove is vented to prevent gas bursts. The valves are designed to operate down to 10^{- 9} mbar / 8 x 10^-10 Torr and up to a pressure of 2100 mbar / 1575 Torr (30 psi).