Ultra-Lite Kit Installation Instructions

DO NOT MIX SPRINGS; use only the springs supplied in this kit. DO NOT retain any OEM springs currently installed in your pistol that are replaced by the CGW kit. DO NOT use any other hammer springs with this kit other than the ones supplied or misfires will occur. NEVER use a hammer spring greater than 15 pounds with this kit.


  • Premium 61050 S-7 tool steel extended firing pin w/spring for FP block CZ’s. PN: EXTFP for the Shadow and 85 series that do not use a FP block.
  • 61100 tempered spring steel FP retaining pin (not used in the Shadow/85)
  • HS-12000 (Black 1 1.5# hammer spring)
  • HS-13 (Blue 13# hammer spring)
  • RP-FPBS reduced power firing pin block spring (not used in the Shadow/85)

The firing pin is a premium Made in the USA part and uses a special firing spring matched to the hammer springs included in this kit. DO NOT use any other FP spring.

This Ultra-Lite kit contains 2 different hammer springs: The “black” spring is CGW part number HS-12000 rated at 11.5#’s. This spring should work reliably with Federal and Winchester primers. This spring will produce a 5.0- 6.0 pounds DA pull with stock internals.

The “blue” spring is CGW part number HS-13, rated at 13#’s. This spring will work reliably with practically any ammo, including small rifle primers. This spring will produce a 7.5 – 8.0 pounds DA pull with stock internals. If reliability is the primary concern, this is the spring to use and is the only spring recommended for self-defense applications.

The smallest spring in the kit is the firing pin block plunger spring located in the slide. You will have to remove the cross-pin in the slide that holds the firing pin and plunger to replace this spring. It makes no difference which direction this pin is driven from.

Test fire your pistol with the ammo you intend to use. If any misfires occur with the HS-12000 spring, install the HS-13.

Dry firing: Your CZ is safe to dry fire when using our part number 61050 firing pin and 61100 FP retaining pin

Contact CGW for technical support or questions by using our contact page on our website.

Or Call 318-738-1464 select option 1

Modification of your firearm may void the warranty of the manufacturer. This product or any CGW product should be installed by a qualified gunsmith. No liability is expressed or implied for damage or injury as a result of improper installation or use of this or any other CGW products.