NetBolt Smart Padlock, Metal Waterproof, Suitable for House Door, Suitcase, Backpack, Gym, Bike, Office, APP is Suitable for Android iOS, Support USB Charging (Gold) Tool Blades & Other Accessories and rough terrain and rough terrain Replaces any standard door knob Can be installed below an existing deadbolt**Installation requires no modification to door Fits doors up to 1 3 4" thickUnlocks with 1 or 2 user programmable codesCodes can contain up to 8 digits Codes can be easily changed whenever necessaryIlluminated keypad Manual keyed emergency bypass (2 keys included) Latch adjustable from 2 3 8" or 2 3 4" back set Includes all required installation hardwareDesigned for interior or covered exterior locationsOperates approx Stores up to 20 fingerprints for friends and family members bicycle and other goods that you want to protect