331-4311 | Damper Actuator, Pneu No 3, 2-3/8" Stroke, 3-7psi, Integral Pivot, Pivot Post | Siemens

This 331 Number 3 Pneumatic Damper Actuator with integral pivot and pivot post is a rugged, metal-fabricated device that provides gradual or positive actuation of HVAC dampers. This actuator has a nominal spring range of 3 to 7 psi, has extended shaft mounting and an ozone-resistant rolling rubber diaphragm. This actuator has an air connection of 1/8" NPT female with a straight dual barb fitting for 1/4" OD tubing.