Level Bolt — Matter over Thread fits inside a compatible existing deadbolt so you can retain the exterior hardware and physical keys while adding smart control. Key features Matter-over-Thread and Bluetooth connectivity for supported Apple Home, Google Home, Amazon Alexa and SmartThings setups. Use the Level Home app and optional Level Keypad while retaining your existing physical key. Remote access, voice control and automations require a compatible Matter-over-Thread hub. Invisible retrofit design keeps smart-lock hardware off the outside of the door. Compatibility and specifications Model C-D21U Matter-over-Thread generation. Backset 2-3/8 in or 2-3/4 in. Door thickness 1-3/4 in. Cross bore 2-1/8 in standard bore. Existing deadbolt Requires a compatible standard-profile deadbolt with at least a 3/4 in profile. What’s included Level Bolt — Matter over Thread Two strike plates Four screws CR2 lithium battery Matter is the smart-home standard; Thread is the low-power network used by this model. Confirm the existing deadbolt profile, door preparation and hub compatibility before ordering.