One-piece design maximizes strength and reduces breakage. Chrome molybdenum alloy steel (Cr-Mo) for exceptional strength. Laser-etched sizes with color-coded rings for quick identification. EVA foam tool storage organizer. Manganese phosphate finish to resist corrosion. Sizes included: T25, T27, T30, T40, T45, T47, T50, T55, T60, T70 "