FULL EXTENSION SLIDES: 4 pairs (8 pieces) heavy duty drawer slides length 250mm/9.8" - fully extended 470mm/18.5" - height 45mm/1.7" - thickness 12.8mm/5" - load capacity 35kg/77lb. EXCELLENT QUALITY: Heavy duty extension drawer slides are made of high quality cold rolled steel, galvanized surface, rustproof, strong, after a maximum of 50,000 cycles stop test. PERFECT DESIGN: Lock Switch - automatically close to prevent accidental opening. Built-in Damper - mute cushion is off. Stainless Steel Ball - Smooth and smooth dust removal, quiet. SCOPE OF APPLICATION: In addition to furniture drawers, drawer slide rail is also suitable for various drawers in machinery manufacturing, vehicle manufacturing and other fields.