The operator I ordered has a different gear arm!

A home owner from Glenrock, WY says:
30866 is stamped on the end of the arm, which matched the part I ordered from you. The middle section of the old, broken arm is stamped with 40395. The part I ordered from you doesn't have a number stamped on this middle section and is about an inch shorter than the middle section of the old, broken part. Do you have one with this longer middle section?
User submitted a photo of window operators.
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Tom from SWISCO responded:
Ah. I see the problem. You ordered the 39-188, when I think you needed the 39-090. The difference is very slight, and it can be hard to notice at first. Basically, I see the 39-090 as having a "Z" shaped gear arm while the 39-188 has a "W" shaped gear arm. Not the best description, I know, but after staring at these guys as long as I have it's the clearest distinction I can make.

Check out our 39-090 and carefully compare its dimensions and style to your original operator and let me know if you agree that it's a match. For future reference, I wouldn't go by stamps alone when finding replacement hardware. Some companies use the same stamps over a whole range of products, and many of those products only have slight differences, like these operators.
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