Floor Wipers Exerise My Friend Has A Shoe Wiping Grate Over A Hole In Her Mudroom. How Can I Do That?

My friend has a shoe wiping grate over a hole in her mudroom. How can I do that? - floor wipers exerise

A friend of the new version of a wardrobe and clean in a special grill to the feet of clay. The slate floor is concrete. What is clean shoe called? How it works - there's a hole in the concrete with a change of frame? Where can I buy the bars? Obviously are very popular in Scandinavia, and can be muddy in New England.