About this item [Privacy Function]: The latch bolt can be locked by thumb turn button on the inside knob. An emergency release tool can unlock the door from the outside. This function is ideal for bathroom or bedroom doors where privacy is desired but a keyed cylinder isn't necessary. [Size]: Adjustable latch (the distane of hole center to the door edge), Fit for door thickness: 35mm to 45mm. [Reversible]: Works with left and right handed doors. [Easy Installation]: Drill hole from both side of door:54mm. Drill hole straight into edge of door:25mm. One-person project! Come with all accessories and instructions. Specification: Material: Aluminum alloy Color: silver Applicable door thickness 50-70mm Handle length 105mm The two sides of the handle are keyholes and hand cranked knobs Screw installation hole spacing 42mm Half cylindrical lock tongue, adjustable length of 60-70mm Appearance surface treatment is electroplating Door opening method: left open+right open Package Includes: 1set Door Lever with keys Havendro Internal Lever Handles for Locking Doors in Silver