The 2 inch caster model would be your choice if you prefer to be closer to the floor or if you will be using it in mostly flat-work applications in kneeling/leaning over positions, such as tile setting, various floor installations, sealing, grouting, staining, etc. Chest support will allow you to work in a supported leaning over position, while sitting and kneeling on the Racatac. Speed & comfort for a demanding job. Comfortable web spring seat. Adjusts from 11.5" to 15.5" high. Made in the USA. Thick foam inner knee pads for all day comfort. 2" polyurethane ball bearing casters. Weighs 14 lbs, load capacity 300 lbs.