Patented Concave sides offer superior support for your softside waterbed mattress, and help maintain the shape of the bed. The rails are concave for added durability, structural integrity and edge support, so you can sit on the edge comfortably.

Additionally, the rails are wrapped in a non-stretch fabric and attached to the rail on the opposite side with a full length of fabric (i.e. the left and right side rails are attached to each other, and the head and foot rails are attached to each other). This ensures that the rails themselves are holding the mattresses in place, not the outer fabric of the mattress. This greatly reduces wear and tear on the outer fabric and keeps your mattress feeling good and looking good for years to come.