Self totaling time clocks print the running total on the card.  Basic self totaling automatic time clocks print the running total on the employee time card when they punch OUT. Better ones separate the overtime along with the regular employee hours.

Examples of basic totaling time clocks are:
Pyramid 4000  PTR4000, Pyramid 4000HD  PTR4000HD, Pyramid 4001, Lathem 7000
Better automatic self totaling time clocks include:
Amano MRX-35, MRX35, Amano MJR7000, MJR7000, Amano MJR8000, MJR8000
Isgus 2040, Acroprint ES1000, ES1000