Wolff recoil spring guide rods for M&P series pistols are the ideal companion for Wolff recoil springs above. Guide rods are solid steel, hardened to a minimum of 55-RC and now have a jet black finish that won't wear off and provides corrosion protection. Wolff guide rods provide optimum performance for Wolff recoil springs through better support and spring alignment. Permits you to keep factory recoil assembly intact.  For use with full size models only. Available as a seperate item, or with your choice of recoil spring