These wheels are made to outperform and outlast the competition. HEAVY-DUTY CASTERS: The HANDSAMMU's heavy duty casters are made of high-quality Cast Iron, bright galvanized steel wheels and yokes. The Heavy Duty Caster wheels are highly compressed sintered iron，also have strong abrasion resistance, are not easy to rust, and have strong shock absorption and buffering performance, which increases the service life.
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