Replacement Operator

Thanks for reaching out to us. Looks like you have a split arm operator, not a dual arm. I think you may be mistaking the hinge arm as part of the operator, but it's actually a distinct and separate piece. You can even see in your first photo that they're not connected in any way. If you aren't sure what I mean, then you can remove the operator and examine it by itself and you'll understand right away. Regardless, the 39-342 has one arm too many and so it will not replace your original operator.

With that in mind, my suggestion to replace the operator would be our 39-329, along with a new 39-232 handle. I don't think your old handle will be compatible with the new style operator. The manufacturer, Roto, changed these in recent years so that the operator is "male" while the handle is "female." On older models like yours, these roles are flipped. I have no idea why they changed it in recent years, but it is what it is.

Assuming you also needed a hinge, my recommendation would be the 36-048. This won't be identical to your original model, which isn't made anymore, but as long as the base track is 10" long and as long as you replace the top and bottom at the same time then you should be good to go.