Helical Insert, Free Running, 304 Stainless Steel, Internal Thread Size 5/16-18, Thread Type UNC, Thread Direction Right Hand, Length 0.469 In, Free Coil Dia. 0.390 In, Tap Sizes 5/16-18 STI, Aluminum Drill Size Q, Tensile Strength 200, 000 to 250, 000 PSI, Rockwell Hardness C43-C50, For Metal, Package Quantity 12