OTB MT-D Battery 2.4V 600mAh NiMH for AVM Fritz! Fon / Medion MD 81877 / Audioline SLIM DECT 500 / T-Com Sinus A201 and many more. (Electronics)
The battery fits into the slot of the phone into Fritz properly. The phone works like new again, I have not measured accurately, but the capacity appears to be similar to that of the original. While it can not yet say for life after a few days, but n