Need new channel balances

The marking reads 29 3 B.S.I 0L
The window weight is about 20 lbs
Window is non-tilt
On the shopping section, it looks like either an S380 or S385 but I can't tell the difference



Thank you for reaching out to us! I agree that this is either the Series 380 or Series 385 but I'm afraid I can't determine which one you have. The difference between these two balances is the depth of the bottom fitting so you will need to measure as shown below. I also recommend the 2930 option. A pair of balances with this stamp will support a sash weighing 16 to 23 pounds.


On most, it looks slightly less than an inch - about 15/16". But I noticed one fitting was different. It looks like it is a full inch. So now I'm thinking the others are just worn down from use.
All of the balances have the same markings.
From these pics, does this look like the case to you?



It's indeed possible that your shoe has worn down over time but I recommend you re-measure just to confirm. We also have the 15-029 shoe which resembles one of the shoes shown here but this measures 7/8" deep. Can you also confirm if the balances shown here with different shoes are from the same or different windows?

It's hard to capture in the picture but all of them (except one) look like they are somewhat worn down. Some are uneven. I didn't realize it until I found the one different one with a cracked wing that looks unworn and gave them all a closer look.



Hey there! Emily isn't here today, but I'll do my best to help out.
I've never seen a shoe with that kind of wear before. It's weirdly flat, which makes me think that these were in fact cut down. I wonder if whoever installed these to begin with bought the wrong size and had to cut them with a utility knife to get them to fit. I'd be lying if I said I've never done the same thing. That would also explain why they're so uneven; whoever did it was probably in a rush.
Either way, it seems we have two options ahead of us right now:
1) We assume that the shoes were worn down, and therefore go with the 1" depth option. That's our Series 380. In a worst case scenario, they're a little too thick and you end up having to reduce the shoe depth yourself.
2) We assume that the shoes were, in fact, altered. In that case I can set you up with a custom order balance that uses the 15-029. This has a 7/8" depth, which is about the same as what you have now. However, the worst case scenario here is that the shoes are too small, which isn't something you can adjust. The balances would still work (sort of) but the window wouldn't be braced properly, which would lead to the window shifting from side to side during operation.
It's ultimately up to you which route you want to take. I'm happy to accommodate you either way, just say the word.

How difficult are they to trim down (if necessary). Would that be a utility knife or could I sand it down?
Also if we wanted to order some of each to see which one works best - what is the price difference between the two?
Also I'm assuming the footings have to be factory installed and I can't just order extra footings and swap myself. Correct?



I personally use a utility knife, but I have a few colleagues who like to sand them down, too. It all depends on preference. Just make sure to wear safety gloves if you decide to go with a utility knife, just in case. Also note that any balance altered this way unfortunately cannot be returned for a refund. You can see more information here.
Lastly, yes, you can just order the 15-029 separately and install it yourself if you wanted to. It takes a few specialized tools but it's honestly not that complicated once you know what to do. We even have a video guide that shows you how to do it.