Selecting the correct material is vital for durability and floor protection. For hard, uneven outdoor surfaces, choose Pneumatic or Solid Rubber wheels as they provide excellent shock absorption. For smooth indoor warehouse floors, Polyurethane (PU) wheels are ideal because they are non-marking, chemical resistant, and offer low rolling resistance. In heavy-duty industrial environments, Cast Iron or Steel wheels are preferred for their extreme load-bearing capacity, though they may damage delicate floors.