All Purpose Double Bucket Dolly w/ Dirt Dropper & Grit guard (6) 3" inch casters Double the productivity and capacity Dirt Dropper is attached with a simply bolt and nut making it easily removalable. Four quadrants at the base of the Grit Guard calm the wash water and hold the grid above the bottom of the bucket. The Detail Double Dolly is a great combination for double the productivity and capacity. This is a wonderful tool for the double bucket wash method in conjunction with the dirt dropper and grit guard.