What is the difference between the 39-090 and the 39-188?

A quick learner says:
What is the difference between the sash crank and the dyad crank other than cost? (pt.39-090 vs. 39-188)
Profile picture of Paul
Paul from SWISCO responded:
Good question. The 39-090 and the 39-188 are very similar window sash crank operators. Take a look at the picture in this post for an alternative view of both operators. In the images below you will see that 39-090 has a longer forearm than the 39-188.
Back view displaying forearm length of the 39-090 sash crank operator.
Back view displaying forearm length of the 39-188 sash crank operator.
Profile picture of Paul
Paul from SWISCO responded:

The length of the forearm of the 39-188 crank operator is 3-5/8".

Photo of the 39-188 with the 3-5/8 inch forearm.
A quick learner from new york says:
what is the length on the forearm on the 39-188 sash dyad crank 5"?
Connecting a casement window operator to stud bracket
Connecting a casement window operator to stud bracket
VIDEO
WATCH >
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.