Caster-replacement slippers for office chair

Tired of rolling erratically while wearing off your hardwood floor? Replace your casters with slippers. The stems have slight fins that progressively squeeze them in as you push (unlike the snap system of the commercial ones) but it holds equally well. They fit a chair bought at Staples, so I'd assume it is the standard caster stem size.

You'll need slipper cushions you can buy at a dollar store, 27mm max diameter. The underpart have a slight dent so the cushions hold better. I warmed the pla