Zaffiri Precision Upk for GLK G1-4 (No Guide Rod) - Essential Upgrade Kit for Glock Gen 1-4

The Zaffiri Precision UPK (Upper Parts Kit) for Glock Gen 1-4 is a complete internal upgrade solution for custom Glock builds and slide projects. This kit supplies all the small parts and springs needed to finish your slide assembly—everything except the guide rod and recoil spring assembly—making it ideal for gunsmiths and experienced builders working with Glock 19, 17, 17L, 26, and 34 platforms across generations 1 through 4. Every component is manufactured in the US to match OEM Glock tolerances and specifications, so you get reliable function without compromise.

Whether you're assembling a custom slide from another manufacturer or refreshing the internals of a well-used frame, this kit takes the guesswork out of sourcing individual parts. Zaffiri Precision engineers each piece to fit and function just like factory Glock components, but sourced and QC'd as a matched set. The inclusion of both spring cups, the firing pin channel liner, and a nickel-plated aluminum slide cover plate means you're getting a comprehensive package—not a pile of orphaned springs and pins.

Installation requires gunsmith-level competency; this is not a drop-in DIY upgrade for new shooters. Once installed by someone who knows what they're doing, you'll have a solid, properly functioning upper assembly. Keep in mind that this kit does not include the guide rod or recoil spring assembly, so you'll need to source those separately or retain them from a donor slide.

Key Features

• Complete internal parts kit for Glock Gen 1-4 custom builds
• US-manufactured components to OEM Glock specification
• Includes firing pin, firing pin spring, spacer sleeve, spring cups (pair), firing pin safety, extractor, depressor plunger, plunger spring, bearing, firing pin channel liner, and aluminum slide cover plate
• Guide rod and recoil spring assembly not included—source separately
• Compatible with Glock 19, 17, 17L, 26, and 34 Gen 1-4
• Designed for professional gunsmith installation

Specifications

Frequently Asked Questions

What Glock models does the Zaffiri Precision UPK fit?

This kit is compatible with Glock 19, 17, 17L, 26, and 34 across generations 1, 2, 3, and 4.

Does this kit include the guide rod and recoil spring?

No. The guide rod and recoil spring assembly are not included in this UPK. You will need to source or retain these separately.

What parts are included in this kit?

The kit includes: firing pin, firing pin spring, spacer sleeve, two spring cups, firing pin safety, nitride-finished extractor, depressor plunger, depressor plunger spring, spring-loaded bearing, firing pin channel liner, and an aluminum slide cover plate.

Can I install this myself?

This kit is designed for installation by a competent gunsmith. It is not recommended for inexperienced users. Improper installation can result in malfunction or safety issues.