I love these Colson casters for moving commercial refrigerators around our shop. Four casters per dolly easily handles 1000 lb units. They have lasted 8-10 years without splitting. If I have a negative to add, it would be that the 3-1/2" full lock caster is about 1/8" taller than the non-locking casters. It makes my rolling cart teeter just so slightly. With weight from my tool box added, it's fine.
*** TOP SELLER***
3-1/2'' x 1-1/4'' EcoForma Swivel Caster with Annular Ball Bearing
Capacity: 250 LBS Each
Wheel Diameter: 3-1/2''
Wheel Width: 1-1/4"
Wheel Material: Thermo-Plastic Elastomer (Ecoforma Rubber)
Fork Finish: Zinc Plated Steel
Bearing Type: Annular Ball
Overall Height: 4-11/16''
Swivel Radius: 2-29/32''
Such a High Quality product. I am loving them more and more as a replacement from what a had. Very easy to maneuver and install!