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Question

I need a replacement crank unit. there are no marking on the window or the crank. i do not know the manufacturer, i just need a replacement, can you help?

Bob · Accepted Answer

This looks like either the 39-253LB & 39-253RB, or the 39-438B & 39-439B. The only difference between these operators are the appendages at the end of the link arms. The video below goes into detail.