500lbs Heavy-Duty: Made of 0.77 in/19.5 mm thick high hardness steel, the heavy duty drawer slides have a weight capacity of up to 500 lbs. The galvanized finish makes the telescoping drawer slides rust and wear-resistant for long-time use. It can be used in shelving, cabinets, industrial drawers, RVs, trucks, vending machines and more. Secure Lock Design: The full extension dresser drawer slides are equipped with a locking design that locks the slides with a simple press, ensuring that your items are secure and won't slip off even in bumpy roads. Gentle & Quiet Lock Slides: These slides feature a locking and latching design that is easy to control. Unlike slides with no lock or only one lock, our lock design provides greater security and stability. Double-row ball bearing provides smooth sliding when closing and opening drawers. Nylon cushioning on center slides is designed to produce less noise and won't bounce. 3-Fold Drawer Slides: You can get 1 pair of drawer slides with lock: 49 inches/1252 mm long, 3 inches/76 mm wide, 0.77 inches/19.5 mm thick. With 3-fold full extension design, you can reach the whole drawer. It is a good assistant for utilizing drawer space! Choose the Right Size: Full extension drawer slides are compatible with most major drawer and cabinets. Please see the pictures for a detailed description of each size when choosing. Please measure the length of your drawers and cabinets (excluding frame boards) before choosing our drawer slides. Note: The length of the slide should not be less than or equal to the depth of the drawer.