Bob from SWISCO responded:
June 30, 2021
Hi Zhigang. I am confident we can help with the channel balance, but that stamp only tells us its spring strength, not its identity. I need to see the nylon fitting on the other end for full identification. For the Top Sash Guide, start by comparing to our 18-009. Let us know if any dimensions differ. |
Bob from SWISCO responded:
July 6, 2021
Hi Zhigang. I believe you might have our S350-34. This channel balance has a bottom fitting with wings (those side stabs) and a top fitting without them, which matches what you show in your photos. Please review the dimensions to confirm it matches up. For a stamp option choose 3340. |