Nikon P Tactical 2 Piece Mount, 30mm Tube, Black - 16562p Nikon P-Series 2 Piece Split Ring Scope mount is designed to allow you to excellent fore and aft positing. These particular ring mounts are designed to fit a Scope with a 30mm tube diameter. It is constructed from aluminum. These mounts are designed to give you optimal height when mounting a scope on your rifle.