casement window crank

A home owner from Upstate New York says:
August 19, 2021
Opens left. Arm seems to measure 8" from the bend to the opposite end. Screw holes seem to measure 4-3/4" for the outer holes and 4" for the inner holes. (I'm not great at measuring.) This is to replace a crank on a steel-frame "architectural" (?) window, it has multiple small panes, it's probably from the 1940's. I do not see any markings, names or numbers.
Thank you.
Thumbnail of the uploaded file named DSCN1350.JPG
Thumbnail of the uploaded file named DSCN1352.JPG
Profile picture of Bob
Bob from SWISCO responded:
August 24, 2021

This appears to possibly be our 39-353 & 39-354 Hope Operators. Please compare the dimensions and see if you concur. 
A home owner from Upstate New York says:
August 24, 2021
The 4-1/8 on center looks correct; however, from gear center to arm button is only 8" or possibly 8-1/4".
I'm confused about this because we've previously purchased replacements for these casement cranks from you and I see in my archive they were 9" arms. But this one definitely measures 8-8-1/4" not 9".
Profile picture of Dave Sr.
Dave Sr. from SWISCO responded:
August 25, 2021

At one time operators were made with a 8-1/2" long arm. However it seems that now the norm is 9". Check your casement window. See if it is wide enough to accept the 9" long arm. Take the measurement from the center of the operator like they show on our website. Also, looking at your photos it appears that you have 4 mounting holes. Check the difference in the mounting holes between the 39-002 and the 39-353 to see which one matches up to the mounting holes in your operator.
Hope Operator, 4-1/8" HCs
Hope Operator, 4-1/8" HCs
39-353
$24.70
Hope Operator, 4-1/8" HCs
Hope Operator, 4-1/8" HCs
39-354
$24.70
Window Crank Operator, 9"
Window Crank Operator, 9"
39-001
$17.45
Window Crank Operator, 9"
Window Crank Operator, 9"
39-002
$17.45
Anatomy of a casement window
Anatomy of a casement window
VIDEO
WATCH >
How to identify casement and awning operators
How to identify casement and awning operators
GUIDE
READ >
Reply to Thread
Use this form to ask a follow-up question or to share your experience regarding this subject.
(your email address will be kept private and is only used to inform you when a response has been made)
Current wait time is 3-4 business days
We promise that one of our experts will personally get back to you as soon as they are able. Thank you very much for your patience and understanding. If your inquiry is time-sensitive, please feel free to reach us at (888) 991-1929 or at help@swisco.com.