Standard sizes. Standard bed sizes in the US and Canada are: Twin or single 38 in × 75 in (97 cm × 191 cm) There is a common misconception that a single bed is sometimes smaller than a twin. Buy Aerobed Classic Air Mattress, Twin: Air Mattresses – Amazon.com FREE DELIVERY possible on eligible purchases I purchased this mattress in September 2017. In July 2018 (less than a year after owning this mattress) I noticed there was mold on the underside of it. Don’t think this bag will keep out anything, including moisture. The two rows of "vent holes" that go through both sides of the bag will let in anything smaller than a quarter inch or anything able to enlarge a quarter inch hole. Our Rating: (8.5 / Out Of 10) Avocado sent us their mattress to review, and after putting it through our rigorous testing, I think this could be a great product for many mattress consumers. .