Dark Storm Industries Single Stage Trigger Kit 4.5lb Curved Black. No cast parts. No shortcuts. Just clean breaks solid resets and mil-spec reliability. Includes trigger hammer disconnector and springs. Specifications for Dark Storm Industries Single Stage Trigger Kit: Manufacturer: Dark Storm Industries Color: Black Trigger Shape: Curved Trigger Material: Steel Trigger Pull Weight: 4.5 lb Trigger Pin Size: .154 in Gun Make: AR Platform Gun Model: AR-15 Finish: Nitride Features of Dark Storm Industries Single Stage Trigger Kit Single Stage Mil-Spec Trigger Wire EDM cut components No MIM (Metal Injection Molding) For use with small pin (.154 in) hammer and trigger pins (not included) Package Contents: Dark Storm Industries Single Stage Trigger Kit What firearm models does the manufacturer say Dark Storm Industries Single Stage Trigger Kit is compatible with? The manufacturer suggests that Dark Storm Industries Single Stage Trigger Kit is compatible with AR-15Dark Storm Industries DSI-TRG-1S: Single Stage Trigger Kit 4.5lb Curved Black