Check the listing for details. ZEV Technologies Pro Starter Spring Kit for Glock Gen 1-4 - SPR-START-KIT-PRO. Color: Silver, Condition: New. Listed at 29.40 USD. ZEV Technologies Pro Starter Spring Kit for Glock Gen 1-4 - SPR-START-KIT-PRO Description: The ZEV Technologies Starter Spring Kit features the ZEV Pro Connector, 2lb Striker Spring, FPS Spring, and Trigger Spring. The Pro Connector has been engineered to provide users with a consistent, positive reset and a reduction in trigger pull weight without sacrificing the reliability or safety of your pistol. Whether used in conjunction with a ZEV trigger or with your stock Glock trigger, the PRO connector will provide a noticeable increase in performance and is ready to drop-in and use straight from ZEV, no fitting or polishing required. Fits the Glock Gen 1-4 (Except 42, 43). Included ComponentsCONN-PROSPR-TRGSPR-FPSSPR-STK-PROCaliber- 9mm,10mm, 380, 40, 45 Auto, 45 GAP, 357 NOTE: This item is not compatible with Gen5, G42 or G43 Glock Models