Four-way, direct-acting Skinner Model 71417/71477 has reliable operator assembly, brass body, and dual frequency rated coils. Dual-solenoid valve holds its last position despite loss of power or pneumatic pressure, and requires no minimum operating pressure to shift position. It handles standard voltage requirements or can be customized for other ac voltages. Options include locking manual override; flow control to regulate cylinder speed; Viton seals; and metering.