Keep your existing lock and keys. Easily attaches to your existing deadbolt; use your existing keys at anytime.Simply Speak to lock your door. Tell Alexa, Siri or the Google Assistant to control your August Smart Lock Pro (requires August Connect Wi-Fi Bridge). Locks automatically behind you, and unlocks as you approach. Retrofit installation works with most standard single cylinder deadbolts. Works with Alexa for voice control (hub required, Alexa device and hub sold separately). Simply Speak to lock your door. Tell Alexa, Siri or the Google Assistant to control your August Smart Lock Pro (requires August Connect Wi-Fi Bridge). Keep your existing lock and keys. Easily attaches to your existing deadbolt; use your existing keys at anytime. Control access for anyone. Grant access for a few weeks, a few hours, or a few minutes. It's up to you. Locks automatically behind you, and unlocks as you approach. Retrofit installation works with most standard single cylinder deadbolts Be sure you're secure with DoorSense. Only August has DoorSense to tell you if your door is securely closed and locked. Simple, DIY installation. Install in about 10 minutes with just a screwdriver. Always know who is coming and going. Track activity at your doorstep with a 24/7 Activity Feed. Certified Z-Wave Plus home product. Works with Z-Wave, the leading wireless technology for security and home control products.