Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Nice replacement battery pack for APC UPS systems.

I have purchased several of these battery packs and I am pleased with the quality of the item and the cost. They do not use original APC batteries but they seem to work well. Batteries are from different manufacturers and can both be different in the same unit. This is the only reason I didn't give 5 stars (the picture shows the original batteries from APC). So far, so good!