One-piece. Allow use of Weaver rings on these guns. Mfg: Weaver SPECS: Aluminum, Blue. TO-10 Positions scope further forward and 1/4" (6.3mm) higher. Uses 7/8"/1" Tip-Off Mounts or 7/8"/1" Top Mount Rings. TO-1 requires drilling and tapping of receiver. Note: 7/8"= 22.2mm, 1"= 2.5cm.
