Model Number: 2831-01-NY-1-1-#9953 Key Specifications/Special Features: 2.5 inches inverted airline caster, nylon, ball bearing, load capacity is 300.00kgApplications:Inverted roller casters for air cargo handling in the aviation industriesThese casters can withstand the severest strain as evidenced by rigorous testing that showedNo signs of caster failure after passing a standard roller over a ramp 25,000 timesInverted casters are tested to provide a long service lifespan