Bob from SWISCO responded:
July 22, 2019
Thanks for writing in. This looks like either a Series 390 or Series 351 Channel Balance. The only difference between these two balances it the 'depth' of the bottom nylon shoe, so compare both with your old hardware to see what matches best. To know what length to select, measure the metal channel, not including the nylon fittings at either end. Finally, you'll need to pick a stamp option. Look for a stamp code on the metal channel that corresponds with one of these options. If there is no stamp code, or you are uncertain, weigh your window sash. You can then match that exact weight with one of the weight rangers listed alongside each stamp option on the product page. |