We get many calls from hospitals, doctors surgeries, labs and supermarkets asking for speciality castors like 'castors that allow a chair to be static until it is sat on'. They have been asked by safety officers to source such castors but mostly do no know the name of them. The reason they want these is because accidents can happen in the work place when someone starts to sit on a chair with freewheeling castors and the chair moves away from them as they are doing this, resulting in them falling onto the floor! If you replace your free wheeling castors with Brake Unloaded castors it will eliminate this from happening. A castor that is Brake unloaded will remain 'still' whilst it is 'unloaded' (not sat on), the brakes release once the chair is sat on and it becomes freewheeling whilst sat on. As soon as you stand up the brake comes on again. It is not a visible brake, it all works seamlessly internally. Don't just take our word for it, try them and help prevent accidents in the work place.