The stamp option represents how much weight your balance can support. We offer a chart on the S390-27 store page that tells you precisely how much weight is covered by each option. You can use your original stamp as a reference, but if it's too faded to read or missing entirely then the chart is a good way to verify. All you need to do is weigh your sash on a scale and look up your weight.
I'll also post our weight options here for your convenience:
- 2610 will carry a window sash weight range of 5 through 9 pounds
- 2620 will carry a window sash weight range of 9 through 13 pounds
- 2630 will carry a window sash weight range of 13 through 19 pounds
- 2640 will carry a window sash weight range of 19 through 26 pounds
This information is based on 2 balances per sash. Balances are designed assuming friction in the jamb weather-strip will carry a portion of the sash weight. Suggested sash weights are approximate.
