Metal wheels look like a '+' or 'x' with ridged spikes on the sides; they are silver with pointed tips. In the center is a small darker grey metal circle, which connects each spoke of the x. They appear to be very shiny and reflect light.
Metal wheels will always block Canary 214-LE's way. They are generally easy to avoid on their own, but combined with other hazards and sometimes other enemies, this can make avoidance difficult. They are almost always seen in groups, strengthening the likelihood of them hitting Canary 214-LE. They will kill enemies in addition to Canary 214-LE, but enemies are usually placed in between the wheels so that they are still near the wheels, but out of their range.
Moving wheels are the first type of metal wheels seen in the game, making their appearance in level twelve. They will turn at a constant rate, whether Canary 214-LE is pushing them or not. Moving wheels tend to try to push Canary 214-LE forward by their quick speed. Moving wheels cannot easily be affected by objects. Mines are able to slow them down a small amount, but Canary 214-LE's laser or other objects seem to not have an effect on them.
Also introduced in level twelve, manual wheels are the second type of metal wheels encountered. They are stationary, unless Canary 214-LE fires a laser at it or pushes an object (such as a mine or a mine cart) down it to send it spinning. They usually slow Canary 214-LE down rather than speeding up, because firing a laser at one will not send it spinning considerably.