the rod end 10 also includes a flange 16 which acts as a stop for axial movement of the rod end 10 relative to the piston rod the maximum diameter of the rod eye 14 is larger than the diameter of the flange 16 meaning that a device with sufficiently large diameter to fit over the eye 14 will be unable to effectively engage with the flange 16 the rod end 10 further includes an axially extending slot 17 formed in the shaft 12 the slot 17 extends through a wall of the shaft 12 to allow the rod end 10 to be pinned to a piston rod in such a way that it may move axially relative to the piston rod but not rotationally the slot 17 therefore provides a flow path for water to enter the internal cavity of the hollow shaft 12 and from there into the piston rod fig1 also shows a first embodiment of a cover 70 for mounting to the rod end 10 the cover 70 has a main body 20 which is shaped such that it surrounds an upper portion of the rod end 10 the body 20 includes a mounting collar 21 for engagement with the flange 16 which acts as a mounting portion of the rod end 10 the mounting collar 21 has an internal diameter approximately equal to the external diameter of the flange 16 for a tight fit therewith the cover 70 further includes a cylindrical skirt 22 extending in a first axial direction from the mounting collar 21 and an alignment portion 24 extending in the opposite axial direction from the mounting collar 21 as shown in fig2 when mounted to the rod end.