Grade: 25 Material: Stainless Steel (AISI 440) Diameter: 1 inch (25.4 millimeter) Weight: 2.3758 ounces (67.354 grams) PGN’s G25 1"" Stainless Steel Balls extremely precise and smooth surface guarantees you won't find any defects, such as flats, pits, soft spots, and cuts.