Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Unsafe on certain cribs

I recently purchased this item and was excited to use it. It was easy to put together however when I put it on the crib it was very heavy and with one slight bump it fell onto the crib. Luckily my daughter was not in the crib. If you have a crib that has thicker side rails this is not the mobile for you. I have a sleigh type crib and even thought it fits on it, it will definetly fall if touched even slightly. I am returning it today.