If you’re replacing a super single waterbed mattress often referred to as a California twin then this mattress is a superb choice. This 90% Semi waveless mattress is very comfortable and popular because it has 4 layers of super soft fiber running from head to foot together with an extra double layer of contour fiber in the mid section so as to assist your body sink into the mattress more level. It has about 5-7 seconds of movement which is less movement than a free glide, 1 layer or 2 layer mattresses. So it still has some movement plus it contours more to your body and the contour fiber in the mid section will assist your body level you off. 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 . When you’ve got any questions feel free to email. Thank-you for having a look at our products. Mattress Covers Amazon Store.