Adjustable Backset(diatance from door edge to center of drill hole) : 60 or 70mm, fits doors thickness ranged 35 to 45mmApplication: This ball entry door knob for use on exterior or interior doors where keyed entry and security is needed.Opened and closed by turn button on rose from interior,by key from exteriorEach lock opened with the only matched key.Solid Column security bolt for anti-sawing protection.Dimensions: Knob diameter:57mm. Rosette Diameter:65mm. Drill hole from both side of door:2 inch. Drill hole straight into edge of door:1-5/16 inch.Conformed with ANSI Grade 3 Security. Metal construction adds strength, security and durability.Easy to install with all accessories included. Our products are made with the splendid quality materials and are designed to provide you with the best possible user experience.