Thanks for writing in. Your casement operator appears to be the 39-091 ROTO Casement Operator. To determine if this is the correct replacement, look over the dimensions from the diagram below and compare them to your existing operator to determine if this is the correct replacement. The opposite handed version is part 39-092.
You should be aware that the arm connected to the bottom of the swinging window has been discontinued and is no longer made. You'll need to reuse that arm when installing the operator base.
The compatible crank handle is part 39-230 and you may also need to replace the spacer, part 39-557.
Thank you for your assistance! Have a great rest of your day!!
I'm happy to help! Please feel free to reach out with any other hardware repair questions you may have.
Have a great day.
