The Master Lock 5441EC Bluetooth Wall Mount Lock Box combines strength and technology to provide ultimate security for homes and businesses. With military grade encryption and high-security features, this lock withstands physical attacks and hacks, ensuring your property stays protected. Use the Master Lock Vault System and our easy-to-use app for convenient and controlled access. Master Lock 5441EC Bluetooth Portable Lock Box Features: Use your smartphone to open your lock with the Master Lock Vault 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 the lock keypad Low battery notification & reminder on padlock and in-app Comes with easy to replace CR123A battery Includes mounting hardware for easy installation. Large storage capacity for keys and access cards Exterior Dimensions: 5" x 3-1/4" x 2-5/16"