Festo DSRL-25-180-P-FW Quarter Turn Semi-Rotary Actuator, Air, 180 deg, 25mm, Flanged Shaft, DSR Series Overview Festo DSR Series — Semi-Rotary Actuators, Metric: Rotary vane actuator with direct transmission to the drive shaft in the half-shell casing. Features: Rotary vane actuator With spigot or hollow flanged shaft The modern alternative is the quarter turn actuator DRVS ..