Pull Moves. This figure has been reproduced from  to illustrate the central idea behind this neighbourhood. In 3a, the simplest case where position C is occupied by residue i - 1 is shown. This move is equivalent to a corner move in the VSHD moveset. In 3b, residue i is moved to L and i - 1 to C. The chain is in a valid conformation and the move is finished. In 3c, residues i down to i - 3 must be pulled until a valid conformation is found.