Keeps time and settings during power failures with the lathem 5000Ep/6000e rechargeable operational backup battery. This backup battery is for use with lathem VIS6001 5000Ep and VIS6001 LT5000 time clocks. This nimh rechargeable battery works for 72 hours or 200 registrations. Since 1919, lathem's singular focus has been to manufacture innovative, durable and affordable employee time and attendance systems.