Identify Channel Balance Without Brand

Question

This is from a @45 s 35 non tilt double pain window.
The metal channel measures 31 7/8" and is 1/2" inch wide.
There are faded markings and the best I can read of them is "315" and I believe it to read Caldwell.
I need two for this window, I believe the window to weigh 25-30 pounds or so.
Thanks for the help

Tom · Accepted Answer

Just by sight, that looks like S385-32. See if your bottom shoe matches this one below. If so, you need Series 385. The S385-32 comes in a "3150" option, very similar to "315." "3150" holds a 28 to 32 pound window sash, which overlaps with the weight range you listed. Weigh more closely to be sure, and of course, don't forget to measure your shoe, as I mentioned.

Alternate view of 15-004