Check the listing for details. 11 Pound Recoil Spring for CZ SP01 & Shadow 2. Condition: New. Listed at 5.95 USD. 11 Pound Recoil Spring for CZ SP01 and CZ Shadow 2 Pistols Making sure you have the correct weight recoil spring in your gun is going to make a difference on how it handles when performing double taps. Too heavy a spring will cause the muzzle to "nose dive" and take longer for you to recover the sight picture before you can shoot again. Too light a spring may cause damage and introduce feeding failures. Our springs are marked with a different color to help distinguish the weights of each spring for easy identification. Our springs are lighter than factory springs aimed at the shooter who wants to tweak their gun to the ammo they are shooting. If you shoot USPSA or IPSC, you will want to tune your gun to the ammo you are loading and these springs are a great way to optimize your shooting. Reference For Standard Size Models Factory Rating: 14 Lb. - 9mm, .45 ACP, Super .38 and 10mmFactory Rating: 12 Lb. - .40 S&W all models except CZFactory Rating: 16 Lb. - .40 S&W - CZ OnlyFactory Rating: 13 Lb. - CZ 97 .45 ACP (14-16 Lb springs suggested for hardball in CZ971x 11 lb Recoil SpringNOT A MAGAZINE OR GUN See my other auctions for more shooting related parts.