Blum 21 in. Tandem Slides Blumotion feature 21-inch TANDEM plus BLUMOTION full extension concealed drawer slides designed for smooth and quiet operation. These slides four-dimensional adjustment with elongated holes for precise depth adjustment and bottom mount holes available on 15", 18", and 21" slides. They support a static load capacity of 100 pounds, making them suitable for both face frame and frameless cabinets. The BLUMOTION soft closing mechanism ensures a gentle and silent close, while the TANDEM system provides smooth running action. These slides accommodate drawer thicknesses ranging from 13 mm (1/2") to 16 mm (5/8") and are proudly made in the USA.