Please help identify

I'm not sure what you have, unfortunately. We have dozens of different balances with that stamp. It's not a product code or anything, it just indicates the strength of the spring.

In order to figure out what Series this is, I need you to remove an undamaged version of this balance from the window and show me clear pictures of the top and bottom nylon fittings as well as the metal clip at the end of the cord. Please also tell me how many you wanted to buy altogether.

Thanks! This is a huge help. We can supply this balance, but it has to be a custom order due to its configuration. Thankfully, we have all the data we need to get started. 

What I'll do now is email you a purchase link and price quote that you can use to place an order on our site. You may then checkout as normal.