Abstract: A track securable to a window sash for guiding the roller of a window operator having an operator arm selectively pivotable relative to a window frame to move the sash relative to said frame, the arm having the roller at its distal end. The track includes two substantially parallel spaced longitudinal walls connected by a longitudinal wall substantially perpendicular to and extending between the parallel walls, an operator roller being receivable between the parallel walls. An integral stop is stamped in the connecting wall, and includes a non-planar portion angled at one end from the connecting wall into the space between the parallel walls, and an arcuate end surface extending in a direction substantially perpendicular to the path of roller travel from the other end of the non-planar portion to substantially adjacent the connecting wall.