The t40c has a fork that attaches the basket to the boom. You then manually move the fairlead to either side of the basket depending on where the pole work is. The t40d basket has a bracket that attaches to the boom, and the basket is able to rotate from side to side. The fairlead is attached to the center bracket and stays stationary as you rotate the basket to the side of where the work is. The majority of the t40d's I have seen are equiped with the pre lash equipment.
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