Vortex Optics Pro 1-inch Riflescope Rings These Vortex Pro Rings position thecenterof the riflescope tube at a height of 1.12 inches (28.44 mm) from the base. Streamlined, strong and durable, the Pro Rings use four T-15 Torx style socket cap screws for secure mounting of your riflescope. Unique design permits easy installation and removal of the scope into/out of the rings. Permanently attaches to either Picatinny or Weaver bases. Square-edged crossbolt ensures positive engagement of ring to base. Precision CNC machined from high strength 6061-T6 aluminum alloy. Durable black matte anodized finish. Sold two rings per package. Made in USA.