Window Sash Spring

Thanks for posting! Your balances can be replaced with the S378-24, S380-24, or S385-24. To determine which series you have, you'll need to find a balance with an undamaged shoe to measure its depth (front to back measurement). 

Comparison of the S378, S380 and S385 balance shoes.

The 2390 stamp on your balance does not cross-reference with the stamp ratings on our balances. You'll need to confirm the sash weight to determine the stamp for the replacements. There is a chart below the product description, on the website, that lists the range each stamp can support.