Dolly features five 3″ , quiet swivel casters to make transporting containers quiet and effortless. Nonmarking casters glide across floors without damaging surfaces. Large diameter creates a better center of gravity to help prevent tipping over. Vented construction prevents suction between the dolly and container for convenient removal. Dolly is perfect for use in hospitals, nursing facilities, schools, office buildings, airports and more. Dolly universally works with 20-gallon, 32-gallon, 44-gallon and 55-gallon containers (sold separately).