The Motorized Valve Actuator (MVA) (24VAC) features quick-opening motorized valve head that mounts directly onto 1-1/4 Brass and TruFLOW Valved Manifolds. The open/close indicator on these Wirsbo actuators allows for easy visual inspection. It provides individual flow control on a multi-zoned manifold (manifold serving more than one zone). The Wirsbo MVA Actuator includes end switch for activation of relay (pump), heat plant or other auxiliary devices. Power-open, spring-closed, do not mount actuators upside down.