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, anti-rust, solid, after max 50,000 cycles shutdown tests. PERFECT DESIGN: Interlock Switch - closes automatically to prevent accidental opening. Built-in Damper - mute pad is disabled. Stainless Steel ball - smooth and smooth dust removal, quiet. SCOPE OF APPLICATION: In addition to furniture drawers, sliding drawer rail is also suitable for various drawers in machinery manufacturing, furniture manufacturing vehicles and other areas.