Given the task definition and input, reply with output. In this task, you're given a review from Amazon. Your task is to generate a rating for the product on a scale of 1-5 based on the review. The rating means 1: extremely poor, 2: poor, 3: neutral, 4: good, 5: extremely good.

Good heat reflection. Decent length, but a little narrow in the width...but I knew this before buying. The downside and the reason for 2 stars instead of 5 is it deflates during the night enough that my body touches the ground by morning when laying on my side. Did this first and every use.
2