The term “conduit bender” is a bit vague. Originally, it was a bending shoe with a long handle against which you’d push pretty hard and you’d typically use the floor or a wall as the opposing force.

Both are fairly thick-walled and use threaded fittings. To bend either one on a conduit bender, you must use a shoe rated for conduit. If you use a tubing shoe instead, you will likely damage the shoe ...