Arm operator

Thanks for reaching out! Your window operator appears to be a match for the 39-221B Encore Dyad Sill Mount Operator. It has the 39-545 Truth Snap-Stud Bracket at the end of the arm.

To replace the cover, you'll need either the 39-376 (folding) or 39-452 cover and handle kits.

The opposite versions of each of these parts can be found tagged below.

detail of 39-221B