Abstract: A mechanism for attaching a cylinder head on a hydraulic actuator to a cylinder uses a plurality of segmented, curved rings. The rings engage curved surfaces on a plug portion of the cylinder head and on the cylinder. Shear ring retaining plates position the shear ring segments. The cylinder head has a bearing which defines a bore for rotatably connecting the cylinder head to an external structure. The cylinder head also has a neck which joins the bearing with the cylinder plug. The neck has an enlarged dimension transverse to the bore axis and cylinder axis to minimize reaction forces against the shear ring segments generated by torque exerted against the bearing.