The assembly-disassembly-replacement work must be carried out by a professionel armourer having proper infrastructure & tooling Recommended only for rifles having power plant(pump housing) of recommended compression bearing capacity Taming period of 500 shots required to achieve max velocity This Air Rifle Spring is made from high quality German spring steel Treated in the German plant with German technology to give highest stencile stength-ultimate velocity & maximum service life Normal leather washer(piston seal) will not withstand its high bouncing speed-hence always use G.SMITH washer only
