I have a double hung wind where the outside balancers have had the pulley to spring interface break. I originally looked up and ordered 770 x 27" based on the fact that the channel is not ribbed.
Now I see that the balancers I have are 751 but not ribbed.
Channels I have:
Markings: (10/06) Unique 26-D-40
length: 27"
Chanel width: 0.575"
Channel height: 0.525"
Take a look at the photos and let me know what I need. i will ship back the 770 x 27 I ordered, do I need a RMA from you?
Thanks
Alex
