JP Fire Control Kit for .154 small pin or .169 large pin receivers consisting of a JP trigger with engagement and overtravel screws and disconnector spring installed as an assembly, disconnector, CDROM Instructional video, and your choice of a trigger and hammer spring:   3.0-3.5 Pound competition/recreational yellow hammer and trigger spring (standard, shown in photo)    3.5-4.0 Pound enhanced reliability red hammer spring with yellow trigger spring. Provides good ignition reliablity with any ammo. The red hammer spring is the minimum required for a 308 AR-10 set up. Due to the popularity of this version, this version is now offered and should be ordered as product JPFC-1T.    4.0-4.5 Pound tactical for police duty, military or any application in which 100% ignition reliability is demanded with low sensitivity primers or a heavier release is demanded by LE department requirements. May also be used for 308 AR-10 set ups. Kit includes grey hammer spring with yellow trigger spring.    4.5 Pound CMP service rifle competition. Kit includes grey hammer spring with grey trigger spring.