Replacement Hardware Needed

Thanks for posting. It looks like you might have either the 39-253LB or 39-438B Dual-Arm Operator. The difference between these two operators is the appendage at the end of the straight arm. The video below explains. You'll need to see if you can retrieve this appendage, or check an identical operator in the house, to determine what you needed. In either case, for a cover and handle see the 39-375 or 39-451, depending on the style preferred.