Instruct: Classify a review into positive or negative sentiment.
Query: Pricey but worth it.

I purchased the Nikon charger/adaptor because I went through batteries like water. This unit allows me to either use batteries or the wall socket. It is nice to have an extra rechargable battery as back up. At $$$ to $$$ a throw away, it is well worth it expecially if there are no stores close by with batteries.