NiMh batteries are not as touchy as the LiPo's. You can charge NiMh's anywhere from 50ma to 5 amps. For a pack that small you probably want to start around 100-150ma and just see how warm it gets, it might take 2 hours at that rate. It is normal for NiMh packs to get warm to the touch, but hot is not good. If you are not in a huge hurry to fly, and have time to charge, the lower the rate the better. It will provide a more complete full charge and extend the life of the battery. But if it takes forever, you can increase the charge rate in 50ma increments as long as the battery does not get too warm. You really could probably get away with charging it at 300ma or higher with no problems, but start lower and see what happens first.