Industrial Casters, 5"
Real heavy weights for the most demanding applications.
Type: Swivel & Brake
They hold the weight and are priced low. All you want for casters.
I use these for mobile tables in my workshop, for this use they are fine. By eye I'd rate them at ~100lbs each, not 100kg. But for reasonable loads these are great, good brakes.
I bought 4 of those to support a 720 pounds implement and after two attempts at moving it around, one wheel jammed and bent as I was trying to steer it in one direction. The rubber wheel type is too weak to support heavy load, although its max weigh rating was within rated specs. One gets what he pays for..