What caster type should a drafting stool have for different floor types?

On carpet, use standard black twin-wheel casters (they roll easily over carpet pile). On hard floors — hardwood, tile, polished concrete — use soft polyurethane or rubber-tread casters to prevent scratching and provide grip. Avoid hard nylon casters on unprotected hardwood. Many commercial drafting chairs ship with carpet casters as default — specify hard-floor casters at the time of ordering. At OfficeFurniture2go.com, we can specify the correct caster for your floor — call 1-800-460-0858.