This drawer slide kit is constructed of steel tracks with plastic rollers, and it comes in a white powder coated finish. These tracks feature a self-closing design that commences at the final 2-1/2 inch from the end of the 23-3/4 inch long tracks when closing. The maximum load capacity for this kit is 75 lbs., and it fits most bottom/side-mounted drawer systems. This kit cannot be cut down to fit smaller drawer depths as it is designed with a positive stop at the ends of the fixed tracks, and because the rear rollers (11/16 inch diameter wheels) on the sliding tracks are fastened to the ends of the drawer-mounted track pieces. These bottom mount drawer slides can be installed in drawer cabinets with face frames and without. If installing in drawer cabinet with face frame, Prime-Line's model number R-7240 (purchased separately) may be necessary if existing back plates are damaged. The clearance required between the drawer and the drawer opening for these types of slides is as follows: 1/2 inch on left and right sides, 1/4 inch at the bottom and 5/8 inch at the top. Installation instructions are included with each set, and they can also be found within the manufacturer’s website.