Thanks Tom, I appreciate your effort here, great detail!
* I'd say that you have the
19-002 top attachment...
(very close, spot on with the 1 1/4", the 1/2" dimensions are very slightly smaller on mine i.e.1/32 smaller)
* and the
15-001 bottom shoe. Do these look about right? Compare their dimensions to what they have--especially the depth of the
15-001, which is 1-1/8"--and let me know...
(probably close enough but mine is 1-3/32, 1/2" is right, 1" is actually 15/16" on mine)
* The next step is the easiest--your length. You just need to measure the length of the metal channel. Make sure not to measure the nylon attachments in this measurement, just the channel. Based on your stamp, I think that your length will be 17", but double check just to make sure. If so, then look at our
S390-17.
(Checked again and this is 17")
Finally, your option. The option determines what the strength of your balances are, and is often determined by the stamp. Your stamp reads 16D, which often corresponds to our 1640 option. However, you may want to weigh your window sash and compare it to the weight range shown for the 1640 on the S390-17's product page to ensure that it is what you need. If your balance is too strong, your window will be hard to close. If it's too weak, your window may not be able to open at all!
(I think here I'll have to go with the stamp info as I don't have a scale handy)
Please advise, thanks, Steve