LBE Unlimited is a quality manufacturer of AR-15 parts and accessories. This particular item is an AR-15 Carbine Buffer designed to be used in conjunction with a carbine buffer tube. The various weights of the carbine buffers will allow you to customize or tune the cycling of your rifle. The timing of your rifle can be changed and you can refine your brass ejection pattern to a desired location.Specifications and Features:Manufacturer Number: ARBUFF-H3AR-15 Heavy Carbine BufferH2 Weight4.5/4.7 OuncesNatural Finish