Dual Arm Casement Window Operator

Thanks for posting. This looks like either a 39-253RB or 39-439B operator. The only difference between these two units is the appendage at the end of the gear arm. The 39-253RB uses the 39-529 square-shaped slider, sold separately; the 39-439B uses a rectangular slider that comes attached. See the video below for reference. In either case, for a new cover and handle that works with this assembly, see the 39-376 or 39-452 sold separately.