I bought this charger because I wanted a slow, trickle charger...its rated for ~14.5 hrs for 2100 mAh NiMH batteries. The advantage is that the batteries stay cooler, which is better for the device they are going to be used in. [NiMH batteries can get up to 140 degrees when fast-charged].
Amazon's product description says the batteries are 2100 mAh, but mine were only 1700...a big difference, especially when NiMH batteries lose about 1% of their charge per day. Amazon was very good about helping me correct the problem, but be aware that this may happen...you may want to get additional 2100 [or even 2300 or 2400 mAh] batteries just to be safe.