Tool Steel = O1, D2, H13, QRO90, A2 and many many more alloys. The Trail Gear web site says the arm is forged. This will not be tool steel but an alloy made for forging. With out knowing the alloy type heat treating can be inconsistant. Cold bending it may break it. Heating it could make it brittle. Cooling it slowly in sand would be a good idea. Bend at your own risk. If it fails on the road you become a passenger.
Patrick
