Magnetic key holder is designed to hide a key outside or inside and will comfortably store 1-2 keysMagnetic key box securely attaches to any steel surface; Not intended for use on carsMagnetic key holder is constructed of a durable plastic that features a sliding cover with built-in stop to prevent cover from being dropped or misplacedExterior dimensions: 4-11/16 inch (11.9 centimeter) L x 1-3/16 inch (2.9 centimeter) H x 2 inch (5.1 centimeter) WInterior dimensions: 3-3/4 inch (9.5 centimeter) L x 3/4 inch (1.9 centimeter) H x 1-1/2 inch (3.8 centimeter) W; 4.2 cubic inch (10.7 cubic centimeter) volume