No longer made old block and tackle

Handy Person from Fayetteville, NC

Aug 8, 2026 7:10 am

The only identifiable number on this is Pat. #5,737,877. The overall length, measured from the bottom of the black bracket to the end of the gray plastic tube, is approximately 28 inches. The spring itself is approximately 14 inches long.
The bottom sash weighs no more than approximately 15–18 pounds.

3 user uploaded images

4 Replies

Bob from SWISCO

Aug 8, 2026 11:46 pm

Hey there. Is the spring 1/2" in diameter? If so, our Series 795 Channel Balance can replace this obsolete crossbow balance. The video below explains.

Handy Person from Fayetteville, NC

Aug 9, 2026 6:51 am

Yes, the spring is 0.5 inches in diameter.
I really appreciate the quick response and your willingness to share your expertise and help me find the correct replacement parts. I will be placing my order for 14 of these, along with two other window parts that I believe you carry as well.
Five-star customer service and a five-star business right here! Thank you again for your help!
ChrisFrom Door To Floor, LLC

Bob from SWISCO

Aug 9, 2026 12:04 pm

Thanks for the very kind words, Chris. They mean a lot. Do let us know if you have other questions!