Zaffiri Precision, UPK, Upper Parts Kit, For Glock 19 Gen 1-3, Includes Firing Pin and Spring, Firing Pin Spacer Sleeve, Firing Pin Channel Liner, Spring Cups, Safety Plunger and Spring, Extractor, Extractor Depressor Plunger Assembly, Slide Recoil Cover Plate, Guide Rod NEW Firing Pin Spring Firing Pin Spacer Sleeve Spring Cups (2-Pieces) Firing Pin Safety Firing Pin Safety Spring Extractor Depressor Plunger Extractor Depressor Plunger Spring Spring Loaded Bearing Firing Pin Channel Liner Extractor Slide Cover Plate - Billet Aluminum Recoil Spring Assembly (Guide Rod) - Polymer Optional Upgrade To Zp Stainless Steel - Oem Spring Weight Product Description Upper Parts Kit (UPK) for Glock 17 / G17L / G34 - Gen 1 - 3.These are great for completing your custom slide. All parts are from a US manufacturer and 100 percent American made. All Parts are made to the highest tolerance to the original specification.