Exquisites workmanship, high strength and resistance and assemble, stable structure, not easy to loosen, suitable for window with a slot width of 14mm / 0.55inch It is fixed with stainless steel rivets, which is firm and none corrosive, and have strong bearing capacity Double Wheel pulley design, with low frictions, stable operate, quiet and low noise, easy to push & pull Make from stainless steel shell, coppers double grooves and nylon Wheel, enduring, wear resistant, Manufacturer: Kaeltsyn