TacFire&reg; Tactical 30mm/ 1" Dual Ring Cantilever Scope Mount for Picatinny Rail Top Rail TacFire official product, Quick Release Clamp attachment - two finger adjustable quick release cam locks for all picatinny and weaver style rails Ring Size: Both 30mm and 1" size , inserts included Anodized black matte finish.Machined from extruded aluminum T6 6061 One extra top rail mount included for your additional red dot sight or other accessories Overall height:2.35". Overall Length: 5.25" . Optical Height for Co-Witness : 1.6" . Length between two rings: 1.75" Total Weight with inserts : 6.7 oz