We Make these here at our facility they have many uses there good for installing shaft corks for Tungsten or Lead Powder,
removing old epoxy suck in the bottom shafts old Swing weights. Heating Rod from inside to remove stubborn heads.
Also use to calibrate inside measurements inside shafts. They come in 2 sizes 3/16 for heating an Ramming Corks,
and 5/32 fit most graphite mandrels (The Taper Hole in Shaft)
46″ Length 3/16 .175 I.D
46″ Length 5/32 .156 I.D Most Graphite
Quick Note* Be sure you coat the rod maybe once every 6 Months or so with light machine oil to inhibit rust. Depending on which area of the country you live.