Siemens
Item ID: 331-2904
This 331 Number 4 Pneumatic Damper Actuator is UL recognized for fire and smoke applications and is a rugged, metal-fabricated device that provides gradual or positive actuation of HVAC and fire/smoke dampers.
This actuator has a nominal spring range of 3 to 7 psi, integral pivot mounting and a replaceable diaphragm.
This actuator has an air connection of 1/8" NPT female with a dual barb elbow fitting for 1/4" OD tubing..