Originally Posted by
InspGadgt
My IRS clamping hub cracked right where the screw head is on the clamping screw...the first time I used it. The new CRC clamping hub has the slot at a slightly different angle so it has a bit more meat where the clamping screw is. My IRS one still works fine even with the crack but I replaced it with a CRC one anyway.
Was it the clamping hub that came with a 12L4? If yes, those are not IRS hubs.