Hydraulic Car Shifter Mechanical Universal Wheel Property Trailer Obstacle Orange HD-C1 Self-weight:15kg/unit Load capacity:3000kg/4sets Specification:540*580*250mm Roller: High strength metal roller Suitable for tires: 21 inch and below Caster material: new material nylon wheel Caster type: 360 degree universal wheel Caster diameter: 100mm * 4pcs Main frame material: national standard carbon steel