" Solid shelving features 18-gauge galvanized steel construction with a clear, baked-on acrylic coating, uncoated aluminum cast corners, and flat, embossed, or louvered/embossed surfaces. -Sturdy aluminum castings firmly lock the corners to the posts (sold separately) -Each post has rolled, circular grooves along its entire length at 2.5 cm (1") intervals -Unique tapered split sleeve (plastic or aluminum) snaps together around each post -Tapered openings in the shelf corners slide over the tapered split sleeves, providing a positive lock -Shelf is assembled in minutes without the use of nuts, bolts, or special tools Two-fold thickness forms a 3.2 mm (") raised ship's edge on all four sides for all-around rigidity and high strength. Ship's edges help contain spillage, mimimize contamination, and permit easier cleanup. Louvered/embossed shelf designs allow air circulation under packages and containers. Shelves can be loaded and unloaded from all sides for maximum use of storage space. Adjustable feet (bolt levelers) compensate for surface irregularities.Stationary posts over 189.6cm high and mobile posts over 138.6 cm high are not for use with 35.6 cm wide shelves. The height of the chrome-plated and stainless steel stationary posts includes a leveling bolt and cap. The 245.4 cm high stationary posts are not for use with shelves less than 61cm wide. Stability decreases as the ratio of height to width increases -units should be kept as wide and low as possible. Each shelf and post is sold separately. For casters used with mobile units, see 19766-236 series. For special posts used to create shelving units with counter tops, see 19766-814 series. For other accessories, contact your VWR representative."