Window Balance marked 27B

Thanks for posting. Based on your photo, I believe you have our S795-27 channel balance with a 27B stamp. However, it looks like yours installs at the top with a hook, not a screw tab like ours. That means we'll have to specially make it with a 15-198 hook. 

Before we can start, can you tell me the width of your bottom "T" shaped shoe? Can you also tell me how many you need?