Includes: M5 Assembled Upper receiver ATLAS S-ONE handguard 16" .308 Stainless Steel Barrel mid-length Low-profile gas block Mid-length gas tube Comes assembled Does NOT include BCG or charging handle M5 Assembled Upper Receiver Forged from 7075-T6 aluminum Corrosion-resistant anodized finish M4 feedramps Laser engraved T-marks .2795" takedown pin holes DPMS High Profile (.210") Tang) Port door and forward assist come assembled ATLAS S-ONE Handguard Durable aluminum construction Corrosion-resistant anodized finish 1.5" inside diameter and a 1.75" outside diameter Front and rear Picatinny rail Indexing grooves in the 12 o'clock position QD sling sockets at 3, 6, and 9 o'clock positions Compatible with AR-308 upper receivers with a thread pitch of 1-7/16 x 16 and a DPMS High Profile (.210") Tang Rail 16" .308 Stainless Steel Barrel Constructed from 416R stainless steel Corrosion-resistant bead blasted finish 1:10 twist 5/8x24 thread pitch Compatible with mid-length gas systems .750" gas block journal DPMS barrel extension HP and MPI tested