This is a new, unused item. I am selling it because I will not be using it. This is a box-sheet style mat cover that perfectly fits the separately sold "(High-Density Elastic) 55 Self-Inflating Mat DUO," and uses contact cooling fabric with a Q-max value of 0.4 or higher. Simply put it on, making it easy to install. Even in environments with high temperature and humidity, the cool "cooling" and sweat-absorbing "moisture-wicking" fabric will make your summer tent camping more comfortable. It can be machine washed, so you can always use it cleanly. Thank you for looking.