Instruct: Classify a given review into positive or negative sentiment.
Query: Canon Compatible 9-pack BCI ink cartridges for Canon S750

The color cartridges work beautifully. However, the black cartridges are not compatible with my Canon S750 and are completely useless. It will be necessary to purchase it from another source. Why they were sent with my order is a mystery. Canon S750 is not listed on the black cartridges as they are on all of the color cartridges.