M&W twinseal, single hung window

Home Owner from NC

Dec 11, 2017 12:02 pm

It looks like your Series 850.....but the top on mine is NOT like what your shows. On mine: The black shoe is 1.25" wide and the rod's over all length is 24.5". It is ONLY the top connector that is different on yours vs. mine. Keith

4 Replies

Tom from SWISCO

Dec 13, 2017 2:02 pm

You're right, you have an older style with a nylon hook. I recommend our 26-200 screw plug. You can pop this in the window where your old nylon hook went. This will let you install the newer style balance with a screw.

Handy Person from NC

Nov 5, 2023 2:51 pm

Where can I purchase the plastic part that the gray rod slides into? This part has broken on several of my MW windows, all other components are in good condition. I can make the system work again by drilling a .093" diameter hole through the plastic "block" and gray rod then placing a metal pin. But I would prefer to purchase new parts.

Tom from SWISCO

Nov 6, 2023 1:53 pm

Hello! Thanks for reaching out. If you're referring to the plastic part shown in the image above, then it was never sold separately by any manufacturer or supplier. Furthermore, this balance design in general has been obsolete for quite a number of years now. You will need to buy an all new replacement balance, and in a different design to boot. Some retrofitting may be necessary.

I'd be happy to walk you through it, but we'll need photos of the original hardware to get started. I specifically need to see an undamaged version of the balance in question; a photo of its top end, bottom end, and the written diameter of the spring is the best info to start with.