In case you are replacing a super single waterbed mattress often referred to as a California twin then this mattress is a superb choice. This 80% Semi waveless mattress is very comfortable and popular because it has 3 layers of super soft fiber running from head to foot together with an extra layer of contour fiber in the mid section in order to assist your body sink into the mattress more level. It has about 6-7 seconds of movement which is less movement than a free waft, 1 layer or 2 layer mattresses. So it still has movement plus it contours to your body and the contour fiber in the mid section will assist your body level off better. This mattress is made in the U.S. and it is made with quality vinyl and reinforced corners. Most super single mattresses by other brands are imported from China. Not this one. This mattress measures 48 inches wide by 84 inches long and 9 inches deep. This is the usual inside measurement for super single hardside waterbeds . You probably have any questions feel free to email us anytime. Thank-you for taking a look at our products. Mattress Covers Amazon Store.