Master Caster 64334 Safety Casters, 100 lbs./Caster, Nylon, Matte Black, 5/Set

These casters were not available from any other source that we could find. We're using them on a steno chair but the chair is for a 95 yr old and we needed to have casters that wouldn't roll away from her when she is going from standing to sitting in the chair. These casters 'brake' when there is no weight on the chair. After 2 weeks of use it seems to be working with no mishaps. When she sits they roll great, when she stands the chair stops moving and she transitions to her rollator walker. Very pleased with the purchase.