One of the toys that I actually wore out. Essentially a low-slung plastic tricycle. The seat was adjustable; the holes that you didn't use for the seat were perfect for sticking a garden hose into and filling up the plastic chassis with water. There was a tiny drain hole in the bottom (I guess the manufacturer knew kids would leave these things out in the rain), so after "fueling up" at the "gas station" (the garden hose on the backyard patio), I'd ride around the yard until I ran out of "fuel." I wrote "REGULAR" and "UNLEADED" on individual bricks in the wall next to the "gas pump" with chalk.
The Big Wheel was a small plastic tricycle with a large front wheel.