DAMPER ACTUATOR, PROPORTIONING, 25 LB-IN TORQUE,90 DEG STROKE,90 SEC TI MING, CCW SPRING RETURN, NORM CLOSED, USED WITH C7150B WITH CRANK ARM, 2 4VAC, 50/60 HZ. USED AS STANDALONE ECONOMIZER OR WITH A W7459 LOGIC MOD ULE.