GESTRA GAV56F Bellow Sealed PN40 Globe Valve DN20 Bellows-sealed stop valves GAV 56F, PN 40, made of cast steel The new high-quality stop valves series GAV 56F is the latest addition to the GESTRA product range. This innovative valve series is the perfect alternative to tradtional isolating valves and designed for installation upstream and downstream of steam traps, in bypass lines, in controlled systems with temperature controllers or reducing valves as well as upstream of pumps . Please allow 2-3day delivery