Crawler made of high-strength steel have good load-bearing capacity, good toughness and anti-rust characteristics. These multi-functional sheaves have many uses, such as sliding rail doors and mechanical trolleys. Specifications: Name: Track wheel Material: nylon +304 stainless steel bracket Steering: Directional wheel Slot: U-shaped, V-shaped, H-shaped Wheel diameter: 48mm / 9in; 68mm / 2 inches Installation height: 54mm / 1in; 82mm / 68 inches Groove width: 16mm / 0.63in; 22mm / 0.87in Bracket thickness: 7mm / 0.1in; 6mm/0.18in Maximum load: 100-300kg Scope of supply: 2 track note: Due to manual measurement, the size error is 1-2 cm. The color may be slightly different due to screen differences. Thank you for your understanding. The arrival time is about 10-15 days, please be patient. I am very happy to serve you and wish you a happy shopping. welcome to our shop! We strive to create a perfect and pleasant shopping for each customer. We provide a variety of exquisite products for you to choose from. You can browse our store!