All features of the Smart Lock will still work without an Entry Sensor. 

However, the Auto-Lock feature on your Smart Lock will be “smarter” when the device is paired with an Entry Sensor. The Entry Sensor tells your Smart Lock when your door is open, preventing the Smart Lock from trying to lock your door when it’s open. 

For example, if you set your Smart Lock to Auto-Lock after 30 seconds but purposefully left your door open while bringing in groceries, your Smart Lock will not try to lock itself. 

We recommend putting an Entry Sensor on the same door as your Smart Lock to defend your door, and we recommend pairing the two devices to prevent Auto-Lock from engaging while the door is open.