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 0.375 Inches Long, With A 1/4"-20 Internal Thread, A #H Drill Size, And A Right-Hand Thread Direction. This Threaded Insert Is Made From Stainless Steel.