Keyless Entry: The lock has no keyhole for manually inserting a key. Universal Fit: Fits most standard door thicknesses from 14 to 24 millimeters. Pin Code Access: Uses a 4-digit code for access between 1000 and 9999. Durable Construction: Made from solid brass with a laminated plastic body for added security. Easy Installation: Comes with pre-drilled holes for quick and simple mounting to door. Master Lock No. 3 Universal Pin Laminated Padlock 3UP (Pack of 6)