Most timeclock systems utilize these RFID cards. 

Need Help Finding the Right RFID Cards for your Timeclock? 

If you are not sure what proximity RFID cards will work on your timeclock, give our world class U.S. based technical support a call at 970-682-0765. They can quickly help you find the right keycard for your timeclock system.  Free sample cards are also available for you to test on your RFID timeclock system.