This free running threaded insert is for use on aluminum and metal. It has a 200,000 to 250,000 PSI tensile strength and a Rockwell Hardness Scale rating of 43 to 50. This insert is 0.500 inches long, with a 1/4"-20 internal thread, a 0.306-inch drill size, and a right hand thread direction. This threaded insert is made from stainless steel and comes in a pack of 100.