The Imperial Mattress has 2500 pocket springs in a kingsize with a layer of memory foam which is pressure relieving so will adjust to your profile providing support to your spine and it will reduce roll together. The mattress is foam encapsulated which not only increases the durability and life span of the mattress but provides edge to edge support allowing you to utilise the full sleeping width of the mattress reducing roll-off and supporting you as you enter and exit the bed.