It measures 24" metal only.
Hi there!
Thanks for reaching out to us. It looks like your balance uses the 19-041 top fitting. That means this will need to be a custom order since we don't have a stock assembly with such a fitting. I'll just need you to measure as shown below and let me know what you find so that I can get this moving for you. Can you also weigh the window sash on a scale? Your 2390 stamp is outdated so we'll need to know the precise weight in order to re-calibrate the spring strength. Lastly, how many balances are you looking to order?
That's very light for a sash. Are you weighing the balances themselves? The window sash is the glass pane that moves up and down which is what you want to weigh.
I'll email you a purchase link and price quote for (12) 24" long balances with the 19-041 top, 15-005 bottom, and 2360 stamp that you can use to place an order on our website. A pair of balances with this stamp will support a sash weighing 27 to 30 pounds which should work for you as long as the sash weight falls within this weight range.
Let us know if you have any questions!