Does this creeper have wheels or casters?

Wheels and rolling mechanism not specified — test-fit the unit before relying on mobility assumptions. Some users pair creepers with aftermarket caster kits for smoother rolling.

What's the weight capacity for the seat position?

Weight capacity not confirmed in the specs. Treat it as light-duty for seated positioning and hand work. Heavy loads or sustained pressure should be tested before committing to extended use.

Can I use this on rough concrete or asphalt?

Hard panel construction will handle rough shop floors, but surface texture and creeper sole type determine real-world grip. Test on your actual work surface first — uneven concrete may catch edges.