Twenty one inch window guides

Hello,

We'd be happy to look into this for you but we would need you to confirm the numbers stamped on the metal channel of your balance to determine the spring strength needed to support your sash. 

We will also need to see a photo of the front of the bottom fitting shown in your third photo where the pulley and metal clip extends from. That information will give us a better idea of the replacement balances needed for your window. Thank you!