4 Pcs White Sliding Door Roller Double Bearings Trolley Assembly For Pulley Hardware Heavy Duty Trolley Two Wheel Channel Description _x000D_ _x000D_ This product is a 2-wheel trolley assembly, which is made of durable galvanized iron material, with good texture, safe and practical. Easy to install and use, it can be easily applied to your door, a very practical accessory that will meet your needs well. _x000D_ _x000D_ Features _x000D_ _x000D_ -Color:As Shown _x000D_ -Material:Galvanized iron _x000D_ -Size:9.70X4.10X3.40cm/3.81X1.61X1.34in _x000D_ Aperture: 9mm _x000D_ Maximum load: 50kg _x000D_ - Smooth rotation, can bear up to 50kg. Bearing welding positioning to ensure the stability of work. _x000D_ - Easy installation and smooth corners , anti-rust, suitable for various outdoor environments. _x000D_ - Middle support, high strength, impact resistance. Galvanized iron, anti-rust to use. _x000D_ - Galvanized iron to provide smooth opening/closing evenly in the long term. _x000D_ - Stable characteristics, high performance and in great reliability, simple, easy to install. _x000D_ 4 x rollers _x000D_