Use of a cordless drill
Before 2000 many cordless tools had nickel-cadmium battery packs.   Some time in the early 00's, tool makers started making nickel metal hydride battery packs.  As is often the case with batteries, the chemistry involved gave them the same operating voltage (1.2 volts per cell) as nickel-cadmium.  And internally, the cells are compatible in size and shape, so it was an easy swaperoo.  

An older tool made for NiCd will work fine with a NiMH battery pack, even though it's not labeled for NiMH.  That's simply because it was made before NiMH came along. 

A NiMH battery pack will work anywhere a NiCd does, and give ~50% extra runtime. 

A battery charger made for NiCd may not charge NiMH correctly, the biggest danger is overcharge, because NiCd is fairly sanguine about overcharge, but it damages NiMH.