Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Amazon sells these cheaper than my local CVS or Walgreens

I have been using these droppers with my rigid gas-permeable (hard) contacts for almost 9 years now. I put one or two drops on the contact lens before I pop them in my eye, and this solution does a great job of keeping my eyes from drying out.My local Walgreens and CVS stores only sell the Refresh Liquigel in single 0.5fl bottles, and they end up charging around $12 each. I got these off Amazon for $15/2 bottles.