1/2 inch wide X 36 metal body for Lawson window. I need one.

Hello there!

It looks like you have our S380-36 or S385-36 depending on the depth of the bottom fitting. You will have to measure as shown in the image below to see which one matches best. You will also need to refer to the stamp along the metal channel to know which strength option you'll need for your replacements. I'm afraid the one in your photos is too faded to make out. You may want to check the balance on the other side of the window to confirm.

We also always recommend replacing your balances in pairs. If you were to pair a new balance with an old one, the new balance would wear out a lot faster. Just something to keep in mind. 

Comparison of the S380 and S385 balance shoes.

In that case, you'd want the Series 380. Your stamp is odd though and doesn't match our listed options. With that said, you will have to weigh your sash and refer to the chart under the product description on the S380-36 store page to determine the appropriate spring strength option for your balance.