ASCO product E290A484 has a high flow due to angled seat design. Anti-waterhammer design (Fluid entry under the disc). Vacuum operation up to 10mbar. Wide range of piston-type operators (32 - 50- 63 - 90 -125 mm dia.) rotatable through 360Deg, for maximum performance at different minimum pilot pressures. High performance, maintenance-free stuffing box. The valves satisfy Pressure Equipment Directive 97/23/EC, category 1 (DN > 25) or article 3.3 (DN 25).