Bought these for an antique sewing machine table so they are much easier to move around to clean the bottom casters on my hardwood floor without damaging the hardwood. They have an antique look so they look great when installed without instructions. So install the insert over the wheel rack, before inserting I drilled a 5/8 hole, I made one, and I had a really hard time getting the wheel. penetrated like the wind into the other three