39-011 dimensions

Hello,

I looked into this since there are some notable differences between these two operators and it turns out that the 39-011 is an older version of the LH operator that goes with the 39-012. That being said, the differences shouldn't cause any problems since the length of the arm will be compensated by the play in the linkage. The only cause for concern that I can see is that you're saying that your top and bottom mounting holes are 5-1/8" apart and ours are 5-1/4" for both operators. If you'd like to send a picture of your operator uninstalled from the window, we'd be happy to confirm if this is the best replacement option that we carry for your repair. Thank you!