Aero Precision H2 Recoil Buffer AR-15. It is designed to mil-spec standards for use in AR15 carbines with a collapsible buttstock. Please use caution when adding a heavy buffer to your rifle build as too heavy of a buffer can prevent reliable function. Specifications for Aero Precision AR-15 Recoil Buffer: Manufacturer: Aero Precision Gun Make: AR Platform Gun Model: AR-15 Length: 3.25 in Included Accessories: Standard Condition: New Country of Origin: USA Package Contents: Aero Precision AR-15 Recoil Buffer What firearm models does the manufacturer say Aero Precision AR-15 Recoil Buffer is compatible with? The manufacturer says that Aero Precision AR-15 Recoil Buffer is compatible with AR-15Aero Precision APRH100284C: H2 Recoil Buffer AR-15