the 3 best ZKTECO time clock products Last Updated Sat May 28 8:05 AM Eastern #1 The ZKTeco WL20 is a fingerprint time clock. No software. Data is downloaded using smartphone app.UNAVAILABLE #2 The ZKTeco CT20 is a desktop fingerprint time clock. No software. Data is downloaded using USB stick.UNAVAILABLE #3 The ZKTeco PH601N is a non-calculating time clock. Includes cards, keys.UNAVAILABLE