This is a capacity-and-mount-matched collection: heavy-duty casters rated to 7,000 lb, in 6" through 12" wheel diameters, all sharing the 6-1/8" x 7-1/2" top-plate footprint. If your equipment is built around that bolt pattern, every caster here drops in.
Most caster collections are organized by wheel size or capacity. This one is organized by mounting footprint — the 6-1/8" x 7-1/2" top plate — because for a maintenance buyer replacing casters on existing equipment, the bolt pattern is the binding constraint. The wheel can change; the holes can't. Everything in this collection bolts to that exact pattern, so you can swap wheel material or diameter without re-drilling the equipment.
Lower deck height, the bulk of the 7,000 lb-rated builds. Polyurethane on iron for indoor concrete, phenolic for oily floors, forged steel for the hardest duty.
Higher deck but easier roll and better obstacle clearance. The pick when the route crosses dock plates, seams, or debris and the equipment can take the added height.
At 7,000 lb per caster the 6-1/8" x 7-1/2" plate is doing real structural work — the load distributes through its bolt holes into the equipment frame. Use the full bolt pattern (don't skip holes), grade-5 hardware minimum, and confirm the equipment frame can take the point load. Construction at this capacity is kingpinless with roller or tapered roller bearings; a kingpin caster on this plate would be under-built for the rating.
