A linear actuator has a housing with a bore extending therethrough. A first portion of the bore extends into the housing from a first end, and a second portion of the bore extends into the housing from a second end of the housing. The second portion of the bore has a rectangular geometry with substantially rounded corners when viewed from the second end. A shaft is in sliding engagement with the first portion of the housing. A piston member is coupled to the shaft and has a rectangular geometry with substantially rounded corners. The piston member is in sliding engagement with a first interior surface of the second portion of the bore via one or more o-rings. An anti-rotation apparatus is associated with one or more of the piston member and the shaft, wherein the anti-rotation member generally prevents a rotation of the shaft with respect to the housing.