Parts for window

Hi there!

Thanks for reaching out to us. I recommend you have a look at the Series 351 or Series 390 channel balances. The difference between the two is the depth of the bottom fitting so you'll have to measure as shown below. For the 31" balance you will want to select the 3030 option and the 2740 option for the 28" balance. 

Let me know if you have any questions!

Comparison of the S351 and S390 balance shoes.