The Master Lock No. 4401DLH Bluetooth padlock is made of boron alloy, offering maximum resistance to cutting and sawing. The smartphone/app interface offers speed, ease of use, & greater control with the ability to share access, with keyless convenience. The locking mechanism features anti-shim technology, offering maximum security. The 1 Year limited warranty provides peace of mind from a brand you can trust. Features Use your smartphone to open your lock with the free Master Lock Vault eLocks app Never worry about a forgotten combination Share access with others temporary or permanent Share 24/7 access or limit to days or nights Monitor access history & receive tamper alerts Backup access using directional code on lock keypad Low battery notification & reminder on padlock and in app Comes with easy to replace CR2 battery Battery jump allows for temporary access if battery dies while locked 2-Piece weather cover for maximum outdoor protection