The OTC Stinger double flaring toll is designed for double or single flare in copper, aluminum, soft steel brake line, and brass tubing (to 45°). The chrome swivel is made of alloy steel which reduces friction and the forged yoke is made of heat-treated steel for long life and durability. The kit comes with five adapters covering sizes from 3/16 inch through 1/2 inch and 4.8 millimeters through 12.7 millimeters and a blow-molded storage case