Review on HFeng Biometric Fingerprint Door Lock System with RFID Access Control Reader, Electronic Door Opener, and Smart Key Cards (WG26, SD Card) by Ryan Nguyen

Look it works but it usually takes me at least 10 tries to fix my fingerprint. If the relay is on the same device, you can also trigger it with a strong magnet, or just use a screwdriver to connect the positive and negative wires and short the power supply, which will unlock it. Another problem is that the frequency for adding the admin card is shown and can be easily copied with the device. Generally, if you're looking for a fingerprint lock, use a door knob from a company like Ultralock rather than installing a locking system, which isn't as secure.