Claron Style PV and PVM is a single acting rod or piston seal for medium to heavy duty applications. The assembly consists of a male and female header and a series of 'V' rings. The number of 'V' rings may be varied to alter the assembled height. The material is generally fabric reinforced NBR rubber, although style PVM incorporates an 'NBR only' 'V'-ring to assist low pressure sealing. This is now a non preferred design, but it still has a place in application where difficult conditions prevail such as pressure surges and misalignment.