Identifying the two types of casters
The package includes two types of casters. Caster B is omni-directional (it spins around) Caster C rolls in one direction (just front and back) Caster B can also be identified since it has a gap between the wheel and the hex nuts.
Installing Caster B, the omni-directional wheels
Install Casters B on the end opposite the handle. Install Casters C on the same side as the handle.
How the wheels work
The cart is guided by the omni-directional wheels on the handle side. The straight wheels at the rear help drive the unit forward.
Levelling the wheels
If placing the unit on an uneven floor, you may notice a gap between the wheels and the floor. The top hex nut can be adjusted to help level the unit. Simply re-attach the caster with the adjusted hex nut. Tighten using the provided Allen wrench.