JP Reduced power spring kit, yields about 4 to 4.5 lb pull with standard AR-15 trigger parts and 3.0 to 3.5 lbs with JP trigger parts.  Note: Use of this spring kit requires the use of US manufactured (domestic) ammunition or reloades with domestic (non-NATO spec) primers as ignition reliability will be reduced with hard low sensitivity primers as found in may foreign made ammunitions and NATO specification ammunition. Use these parts only in rifles for recreational or competion shooting. Do not use this pring kit for any defense ro duty applications or any AR-10 type rifle.  JP Reliability Enhanced Spring Kit, 3.5-4.0 pound trigger pull with JP fire control parts. This kit includes our Yellow Trigger Spring, Red Hammer Spring, and Disconnector spring. To be used only with JP trigger parts. Will not yield substantial change on standard AR-15 trigger components.  JP Tactical Spring Kit, 4.0-4.5 pound trigger pull with JP fire control parts. To be used only with JP trigger parts. Will not yield substantial change on standard AR-15 trigger components.    JP CMP Service Rifle Spring Kit, 4.5-lb trigger pull when used with JP trigger components. To be used only with JP trigger parts. Will not yield substantial change on standard AR-15 trigger components