Aluminum/steel or titanium firing pins weigh less than half of original factory firing pins, and the weight savings alone would decrease lock times dramatically. But, for even faster lock times and to help ensure positive ignition, the Tubb Firing Pins come with a factory weight chrome silicon spring. CS springs maintain load height and compression strength without taking a set for thousands of compression cycles. Faster lock time means there's less chance of gun movement between the time the trigger is pulled and the firing pin hits the primer. Tubb Firing Pins cut lock time without increasing vibrations AND maintain positive ignition. Designed by NRA Highpower Rifle and Highpower Si Mfg: Superior Shooting SPECS: Firing Pin - 70 series machined aluminum with 4140 steel tips. Spring - Chrome silicon, heat treated, shot peened, stress relieved. Remington models not for use with ISS bolt lock system.