BTF link inserts are cnc machined on a state of the art turning center. They are machined from cold roll steel. The weld surface has been machined to a 45 degree angle. It is recommended to cross drill the end of the tube to add additional area to weld.This insert was designed for 3/4 - 16 thread rod ends.It was designed to fit 1-1/2" od x 1/4" wall DOM meaning they will fit a inside dia of 1 inch.This part number is for LH thread only. Right hand inserts are availiable.