Features 1、STAINLESS STEEL: Wheel roller pulley is made of stainless steel, rust-proof and durable, perfect for home, office, hotel, etc. 2、SIZE SPECIFICATION: Double wheel roller pulley has a longer life span, wheel outer diameter is 12mm, base length 69mm, base thickness 16mm, mounting hole diameter 4.4mm, hole spacing 53mm. 3、SMOOTH AND NOISELESS: Double wheel roller pulley slides freely without jamming, smooth and noiseless, so that you can feel comfortable during the process of pushing and pulling, without disturbing the rest. 4、4 PCS IN SET: Double wheel roller pulley 4pcs set, meet the daily needs, convenient installation, easy and simple. 5、WIDE APPLICATION: Double wheel roller pulley set is widely used for sliding doors, window, cabinets, etc. Specification Item Type: Wheel Roller Pulley Material: Stainless Steel Wheel Outer Diameter: Approx. 12mm / 0.5in Base Length: Approx. 69mm / 2.7in Base Thickness: Approx. 16mm / 0.6in Installation Hole Diameter: Approx. 4.4mm / 0.2in Hole Spacing: Approx. 53mm / 2.1in Package List 4 x Roller Pulley