The upper receiver is BCM M4 marked in front of gas tube. Barrel is Daniel Defense 14.5 " GOV profile 1/7 twist 5.56 NATO. With a Geissele pinned low pro gas block shown in pics. It has a Geissele MK 8 13.5 rail in the DDC finish. High quality build . I paid 700.00 for it willing to sell for 500.00 cash not looking for trades. Im located in Nampa Phone 208-817-3079