Complete Parts With FCG For A Smooth & Reliable Trigger Operation
The Strike Industries Enhanced AR15 Lower Parts Kit is an upgrade for AR-15 builds. This kit offers the complete basic parts you will need, including the fire control group for an unmatched smoothness for mil-spec style AR-15 triggers.
The fire control group offers a crisp 5.5-6.5 lb pull, with polished sear engagement surfaces that vastly improved trigger feel without sacrificing safety or reliability.
The Strike Industries Enhanced AR15 Lower Parts Kit also comes with an enhanced bolt catch with improved grip surfaces and angles to help you deliver your best performance in the field. This kit will give you all of the basic necessities to boost the efficiency of your rifle.
Notes:
- COMPATIBILITY: AR-15: Mil-Spec lower receivers
- NOT COMPATIBLE: AR-10: Bolt Catch, Bolt Catch Roll Pin, Pivot Pin, and Takedown Pin are not compatible with AR-10 lower receivers.
Features:
- Includes SI’s signature Enhanced Lower Parts (AR-EBC, New improved SI-SMC, AR-EPTP, & AR-HS-60/90-3in1)
- SI’s Trigger Springs provide a consistent 5.5 ½ to 8 ½ lbs trigger pull with our fire control group
Package Includes:
Enhanced Lower Parts:
- Enhanced Bolt Catch – features improved grip surfaces and angles
- Strike Magazine Catch
- Strike Magazine Catch Button
- Enhanced Pivot Pin – longer of the two large pins.
- Enhanced Takedown Pin – smaller of the two large pins.
- SI Selector Lever – 2 included in the package
- SI Selector End Plate
- SI 60-90° 3-in-1 Selector Shaft – with screws
Springs:
- Bolt Catch Spring – easily confused with the disconnector spring; disconnector spring is tapered though.
- Buffer Retainer Spring – second largest coil type spring in the kit.
- Disconnector Spring – slightly larger than bolt-catch spring, identifiable because one end is a little bit wide than the other.
- Hammer Spring – largest of all the springs.
- Magazine Catch Spring – this is the largest coil spring in the kit.
- Pivot Detent Spring – same as the takedown detent spring, so there are two in a kit.
- Selector Spring – similar to the takedown and pivot detent springs, but larger diameter; there will only be one of these.
- Takedown Detent Spring – same as the pivot detent spring, so there are two in a kit.
- Trigger Spring – the smaller of the two largest springs.
Pins:
- Bolt Catch Plunger – mushroom-shaped pin
- Bolt Catch Roll Pin – smaller of the two roll pins.
- Hammer Pin – solid pin with machined grooves; can be inserted from either side.
- Pivot Detent – same as takedown detent; both sides are usually rounded or semi-conical.
- Selector Detent – one end is flat, the other pointed/semi-conical.
- Takedown Detent – same as pivot detent; both sides are usually rounded.
- Trigger Pin – same as hammer pin; can be inserted from either side.
- Buffer Retainer – large hollow barrel with a small pin protruding from the top
Fire Control Group:
- Trigger: – Investment cast trigger, CNC machined, heat-treated, phosphated, precision ground
- Hammer: – Investment cast hammer, CNC machined, heat-treated, phosphated, precision ground

























