MegaSleep Duo is a supremely versatile 4-in-1 sleep solution, offering multiple configurations and temperature ratings. It covers couples and solo sleeping with warm and cool night options. Simply flip the bag over to change the amount of insulation on the top side - dark blue side up for cool nights (down to 25ºF), light blue side up for warm nights (down to 40ºF). Additionally, each side can be converted into a solo bag or blanket, creating one for cool nights and one for warm nights.