Alenco replacement window balance
Hello, thank you for posting,
Your balance assembly resembles the Series 395 channel balance. When measuring the length, make sure to measure the metal channel only excluding the nylon attachments.
The metal channel should be stamped with a number that indicates the strength of the spring needed. If there is no markings, you will need to weigh the window sash and compare to the strength chart on the product page to choose the correct stamp option.
Please review and let us know if you have any additional questions!
Great to hear! We are happy that we could assist with your repair and let us know if you have any future hardware questions.