Tachograph card — this is a personal chip card for a professional driver, which the tachograph uses to record driving, working, and rest times. It is mandatory for truck and bus drivers in the EU.
It is issued in the driver's name; you cannot work without it on transport subject to EU rules. Together with KKV (code 95), this is the basic set of documents for truck driver jobs. Working and rest times are controlled by inspections, so violations are automatically visible.