... on hand, throughout the workplace consists of the following: 4 posts, 4 shelves, plastic shelf clips, donut bumpers and 5" swivel ... shelves). Starter Units include 4 posts, 4 shelves and post sleeves. The Add-on Units include 2 posts, 4 shelves, post sleeves and ... come standard with (4) Angled Shelves Casters: (4) swivel 5" x 1 1/4" Rubber Casters with (2) brakes 4 tier wire shelf trolley CE approved