I need to order a window balance

Hi there. Yes, you only measure the metal channels and do not include the nylon fittings when measuring for balance length. These look like either the Series 351 or Series 390. The only difference between these two balances is the depth of the bottom nylon shoe. Compare with your old balances to see what matches best. 

Once you know what balance Series and length you need, you need to select a stamp option. Look for a stamped code on the metal channel with digits that conform to one of our stamp options. If you need help, show us pictures of the stamp codes on your balance. If there is no stamp, you'll need to weigh your window sash. You can then match that exact weight with one of the weight ranges listed alongside each stamp option on the product page.

Finally, to answer your other question: you could technically just replace the nylon fittings, as we do sell them separately. It is, however, a fairly involved process; and in any event, a broken nylon fitting can be a sign that the balance itself isn't far behind. Personally I'd just replace the balances, it's a lot easier. If you are interested in replacing the fittings, however, see the video below.

Hm, that stamp could also possibly say '34 9'. Stamp codes ending in '9' are from a rating system that we no longer use. To be absolutely safe, I'd weigh your window sash. You can then match that exact weight with one of the weight ranges listed alongside each stamp option on the product page.

We have a variety of shipping options, ranging from standard to overnight delivery. You can see the estimated times for each option as well as their cost when you input your zip code during checkout. 

There are no other methods or other ways to just "guess" the weight. The weight plays such an important role in replacing your balance. If you go with something that is too light, the window will not stay open and if you go with something too heavy, then the window won't stay open. We highly do not recommend guessing the weight or just picking any option. The only way to pick the correct stamp option, is weighing your sash on a scale and referring to the sash chart on the product page. We're sorry there are no other alternatives. 

I actually disagree with my colleague Bob here. I took your image and blew it up in an image editing program. While the stamp is faded, I am fairly confident that's a "34 3," not a "34 9." With that in mind, I recommend our 3430 option. This can carry 18 through 23 pounds.

For future reference, the sash is the square glass panel that you physically raise and lower to open and close the window. Many people assume that this itself is the window, but the window is technically the sash, plus the frame, plus the sill, plus all the hardware involved.

Weighing a sash is as simple as removing it and placing it on any common bathroom scale. If you don't have a scale, then there's no way to be 100% sure that the spring calibration you're purchasing is accurate. You can go by the stamp, like I recommend. This is usually the easier method, though it is of course made difficult if the stamp is worn off. 

Either way, assuming my eye is right and your stamp does read "34 3," then I think our 3430 is a safe bet. Don't let my profile picture fool you, though: I actually wear glasses. You should give your stamp a thorough examination just to be sure that's a 3 and not a 9.

You're very welcome. I am glad we could help you with your project. Think of us again for your next project.