28f balances
Hm... this isn't too tricky. I think we can help, but we need two more photos.
First, can you send us one photo of the top attachment? Then, we would also need a second photo of the bottom attachment. If another window (or the other side of the same window) contains the same balance, maybe that balance has an intact bottom "shoe" attachment. It would be better to see an undamaged shoe.
As well, can you confirm the weight of your window sash? The "28F" option is for particularly heavy windows, so we want to be sure of that before recommending anything.
Thanks for the photos! These are definitely half-inch channel balances. I bet it's Series 380 or Series 385. Measure your bottom shoe as shown below to choose which one. Series 380 uses the 1" shoe, and Series 385 uses the 1-3/32" shoe. Pick the proper balance for your shoe.
Then, measure your metal bar. My guess is that it's 29" long, but verify that. If it is, choose S380-29 or S385-29. For a 28F stamp option, consider choosing "2860" on our website. If the balance channel is not 29", choose a different, proper-sized balance from the Series you end up settling on.
As a final note, you really ought to weigh your window sash to check the "2860." Every balance has a webpage with a product description that lists which weights are best to match with which stamp option. Weigh the sash and consult the chart to choose an option, if you want to be sure of what you order.
