Which one do I need?

We sell a ton of different operators like this. I recommend that you look at our complete selection here. We have detailed dimensions and photos for each operator that you can use as a reference for your original part.

The picture you've shown lets me know the type it is, but too many important details are obscured and unknown for me to narrow it down further. If you aren't able to find a match on the link I gave you, then I would need you to remove an undamaged version of your operator from the window in its entirety so that I can see the rest of it. That includes the link arm and the hole pattern I would also need detailed dimensions, such as the hole spacing, link arm size, etc.

Do you have an undamaged version that we can see? That pattern of the two bottom holes is important. I know it seems like a small detail, but there's a pretty big variety of operators that look identical aside from how those bottom two holes are oriented. It's not just about their spacing, its about how they're positioned. 

My first thought would be that you may need the 39-025 RH or the 39-026 LH operators. The bottom hole locations and the link arm are close to your measurements. However, I'm not sure about the attachment hole at the end of your link arm. If it is a threaded type arm that a screw attaches to then I do believe the 39-025 should work for your window. The 39-025 uses a threaded sector at the end which takes a screw. 

Also, you might need the 39-355 slot cover for your window. Take a look at the suggested operators and the related video for more information. Thank you!

Thanks! I do believe you have the "threaded" sector at the end of the link arm like the 39-025. This operator was used on Silverline brand awning windows. Make sure the dimensions and other details match up to yours and you should be good to go.