I had 2" rounds on mine,and found they bent all the time......but easily bent back.....but surprising..........they were some kind of blacksmith made thing with a pierced slot in each end......maybe something very soft like wrought iron........I know they tear up if I try to turn them with carbide tooling,and leave a very rough surface......But found some 2" square,and they are OK.Its handy to have lots of different height bits when straightening things with odd shapes....I pressed a gear from a truck gearbox that had sheared the key and spun on the layshaft ,took nearly 80 tons to break free the small ring of weld that formed from friction........one of the better buys is a big bearing separator ,like an OTC,super strong ,and very handy for any kind of extraction job.....Ive got the second biggest they make...so big no one wanted it at the auction.......To work these pullers as a puller ,you need a helper,but on a press ,they are magic and essential.........Another tip......for separating Harley, Indian,and British bike flywheels use some offcuts of heavy (1/2 or 5/8)truck spring.......mild steel will just bend ,truck spring is 3x as strong.