Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Do not Buy!!! Poor Quality & Poor Nikon Service

This Flash unit has let me down many times when I needed it to work. I have had it service twice under warranty by Nikon and it has stop working again. I may have just a bad unit or the design this unit is of very low quality. If you buy this model you can be the judge but make sure to test often so that you are not stuck with it.