Feature:1. Double wheels pulley design, with low friction, stable operation, silent and low noise, easy to push and pull.2. It is fixed with stainless steel rivets, which is firm and non corrosive, and has strong bearing capacity.3. Selected high quality stainless steel shell, copper double grooves and nylon wheels, durable, long lasting, wear resistant.4. Easy to install and assemble, stable structure, not easy to loosen, suitable for window with a slot width of 14mm.5. Practical window hardware accessories, exquisite workmanship, high strength and corrosion resistance.Specification:Item Type: Window PulleyMaterial: Stainless Steel + NylonWeight: Approx. 96g / 3.4ozApplicable Grooves Width: Approx. 14mm / 0.6inScope of Application: Window, etc..Package List:4 x Window Pulley8 x Screw