The Design House 781906 Tulip 2-Way Latch Privacy Door Knob locks from the inside with a turn-button and does not include keyed cylinders. Finished in satin nickel and designed for left or right hand doors, this knob fits the two most common backsets in the U.S. (2-3/4-inch and 2-3/8-inch). The 1/2-inch latch bolt is plated in nickel and does not budge once in place. Privacy knobs are often used on bedrooms and bathrooms and are opened with generic tools. Use this knob on standard 1-3/8-inch and 1-3/4-inch thick doors. This product has a 1-inch by 2-1/4-inch radius corner face plate. If you are preparing your door for installation, the cross bore should be 2-1/8-inches in diameter and the edge bore should be 1-inch in diameter. This product is ANSI Grade-3 certified, which means this knob is rated for residential security.