Description Firepower(tm)double reinforced Type 1 cut-off wheels are designed for heavy-duty cut-off jobs using circular saws, chop-saws and straight grinding machines. They ensure optimum effectiveness for dry applications on a broad range of ferrous and non-ferrous metals, soft ceramics, masonry materials, reinforced plastic and fiber glass. Most Firepower(tm)cut-off wheels are double reinforced with (2) layers of fiber glass. 4 in. diameter x 1/16 in. thickness x 3/8 in., max rpm 18,000, grade A46T2FG. For metal use.