Sled-Based, dual entry combination desk. MODEL SHAPE HEIGHT DESK P858 A+ 18.5'' 20''x26'' P857 A 17.5'' 20''x26'' P808 - NBRK A+ 18.5'' 20''x26'' P807 - NBRK A 17.5'' 20''x26''OPTIONSPermaTuff EdgePlywood Core Work SurfaceSolid Plastic Work SurfaceBlack EdgeNon-Skid GlidesQ-Ball GlidesThree Work Surface Shape Options: Rectangle, Soft-Rectangle and Teaming