Our Job Box Caster Kits are designed to add mobility to your tool storage, whether it's Greenlee, Knaack, or some other brand, we've got you covered. This 6" Job Box Caster Kit features 6" polypropylene plastic casters, 2 rigid and 2 swivel. The kit is complete with hardware and instructions. Product comes with 3/8"-16 x 1" Carriage Bolts with Flange Nuts.