For independent or partly independent users 4WayGlide System consists of two parts that are fixed to the mattress and a Glide Mattress that lies on top. 4WayGlide Midi is a mid length (150 cm) in-bed system suitable for heavy users with partly mobility in the legs. 4WayGlide Midi has a locking system between the nylon sheet and glide mattress and non slip material along the sides of the nylon sheet.