MATRIX: Lightweight Napa leather with ventilation grommets and memory-foam innersole provides excellent support, comfort and total balance while keeping feet warm and dry. Power strap provides additional support and reduces lace friction. Interchangeable grippers included and 1/8” sliders included with the shoes. Can be upgraded to 5/32”, 3/16” & 1/4” (purchased separately). Designed, developed and tested in collaboration with Canadian and American Curlers, Acacia Curling shoes are a perfect choice for curling athletes of all ages and caliber.