ISMI Complete Spring Kit for Glock GEN 1-4

Fine-tune your Glock’s trigger performance with the ISMI Complete Spring Kit, compatible with Glock Gen 1–5 pistols. This kit includes four precision-calibrated springs, allowing you to customize your trigger pull for either competition or carry use.

Included Springs:

• 4.0 lb. Reduced Power Firing Pin Spring: Shorter length, ideal for lightened target setups.
• 6.0 lb. Extra Power Firing Pin Spring: Longer, for enhanced reliability.
• 6.0 lb. Extra Power Trigger Spring: Lessens overall pull weight and improves reset.
• Reduced Power Firing Pin Safety Plunger Spring: Reduces friction in the trigger cycle.

Performance Setups:

• Target / Competition Setup: Use the 4.0lb Reduced Power Striker Spring, 6.0lb Extra Power Trigger Spring, and Reduced Power Plunger Spring for a light, crisp pull ideal for range and match use. Not recommended for carry or self-defense. Estimated Pull (with 3.5lb connector): ~3.0 lbs.

• Carry / Defensive Setup: Pair the 6.0lb Extra Power Striker Spring with the 6.0lb Trigger Spring and Reduced Power Plunger Spring for a smoother pull with increased reliability. Excellent for 10mm and .45 ACP models, which require more striker energy due to heavier firing pins. Estimated Pull (with 3.5lb connector): ~4.0 lbs.

See our complete line of Glock Products here

Note: NDZ always recommends any part be installed by a qualified and trained gunsmith. NDZ promotes the use of safety practices and gear when working on any firearm.