Is this stool good for working under a car?

Yes, for light jobs. The low padded seat lets you sit beside a wheel or under a raised car, but it does not give the clearance of a full creeper board. Always use jack stands, never just a jack.

How does it compare with a flat creeper?

A creeper lets you lie flat and slide fully under the car. This stool keeps you upright with back support and tool storage, but you cannot get as far underneath.

Will the wheels work on a rough garage floor?

Small casters roll well on smooth concrete but catch on cracks, grit and gravel. Sweep the floor first, and avoid using it on driveways or unpaved ground.

Is the seat height adjustable?

No. The seat height is fixed and low, which suits under-car and floor-level work but is short for taller users.

The stool comes as a seat, backrest, frame and casters with the under-seat tray, plus the hardware and instructions for assembly.

Can it hold heavy users?

It is built for typical home use. Heavier users report the padding compressing over time, so check the stated weight limit before relying on it daily.