Non-slipping devices for footwear, namely, non-slip soles for footwear; snow boots; footwear; sports shoes; boots for sport; ski boots; shoe soles; soles for footwear; insoles for footwear; heel pieces for shoes; shoe covers, other than for medical purposes, namely, shoe covers for use when wearing shoes; boots; galoshes; fittings of metal for boots in the nature of toe caps, heelpieces; fittings of metal for footwear in the nature of toe caps, heelpieces