... double bearing 2)it is PU caster 3)Good cost performance: anti-friction, good impact resistance, high load bearing Specificaton: ... 4.anti-friction, good impact resistance, high load bearing. 5.payment: after 30% T/T, advance delivery. 6 ... 154 50-90Configuration screw way M8-M12, 5/16-1/2. Stem way Diameter 8-18. The ... the installation size of this series. 2.5"Double bearing PU wheels for trolley cart