Our AR 15 Upper Receivers are machined from forged 7075 Aluminum with mil spec hard anodizing. Lightweight design 6.2 oz stripped (.8 oz lighter than a mil spec upper receiver) 1.7 oz lighter than a mil spec upper receiver with hardware installed. Captured dust cover door pin eliminating the need for the E clip. We carry partials and AR15 complete upper receivers. If you need to know how to assemble an AR-15 Upper Receiver, read our post on the tools you will need.