Instruct: Classify an Amazon review into positive or negative sentiment.
Query: Collar works well

This collar works very well and helps to control barking. We only need to use the warning level and our dog does not bark. However, I wish they had devised a different method for turning it off and on. Our collar requires the use of a coin or something similar to turn it off and on which is very inconvenient. Otherwise it works as advertised.