Casey from SWISCO responded:
December 18, 2019
Thank for posting on our discussion board. Have a look at both our S351-29 and S390-29 channel balances. The only difference between these two balances is the depth measurement of the bottom balance shoe. The depth of the bottom shoe for the Series 351 measures 1" and for the Series 390 is 1-1/8". Measure the depth of your bottom shoe, like in the diagram below, to determine which Series will work for you. Since your balance does not have a stamping on it, you will need to weigh your sash on a scale and refer to the sash weight chart listed on the product page. 72 |