Heel Plug / heel cover

The heel covers of Heel Plug, by very easily being put on/taken off, minimize the noise of heels' tips hitting hard floors inside buildings.
With Heel Plug placed at both sides of the entrance to buildings, women can very conveniently put on and take off the heel covers when going in and out of the building, just like switching to slippers from shoes at home. When going into a building, what women on heels need to do to put on the heel coversis just lightly stepping on the heels. When going out of the building, the same simple act of stepping on the heels suffices to take the heel covers off.