The High-Tech Shelf Brackets from Hafele are made of plastic and are available in Small and Big sizes. The Small shelf brackets are for shelves 2mm to 18mm thick and have a weight capacity of 44 lbs. The Big shelf brackets fit shelves 5mm to 35mm thick and have a weight capacity of 66 lbs. The brackets come in Blue, Red, Green, Yellow and Black transparent finishes as well as in Black and Silver non-transparent finishes. The shelf brackets are packaged in sets of two and include mounting hardware.