not extend the entire length of the piston rod body 22 in this embodiment the body 22 is provided with a recessed portion 42 configured to form an annular shoulder 44 a distance 34 x 34 from the face surface 28 of piston 12 this distance 34 x 34 is determined by the length of the stroke of the piston as illustrated in fig4 wherein the piston is shown to be at the end of its stroke as can be seen in fig2 the outer shell extends from shoulder 44 to shoulder 38 and is secured in recessed portion 42 on the rod body by nut 21 shell 40 covers the portion of the piston rod body which extends through opening 46 in end cap 48 of a cylinder 50 fig4 by providing a durable outer shell which does not require the amount of shell material as is needed in the embodiment of fig1 yet greater weight savings are achieved at less cost fig3 illustrates another embodiment of the present invention wherein like numerals refer to like parts as seen in fig3 the body 22 of the rod is only partially encompassed by an outer shell 52 at the forward end 16 thereof in this embodiment outer shell 52 is provided in an annular recessed portion 54 at the forward end portion 16 of body 22 shell 52 includes ends 53 and 56 and end 53 is disposed in abutting relation with surface 28 of piston 12 end 56 is disposed in abutting relation with a shoulder 58 provided at the juncture of recessed portion 52 and the larger diameter of.