Replacement Parts for MI Window

Handy Person from Pittsburgh
May 23, 2013 8:21 am
We live in a Maronda home that has "MI" (???) windows in it. We need to replace one window sash that lost its seal (turned white inside). But much more urgently, I need to purchase a bunch of the little plastic catches that are screwed onto the upper corners of the lower sashes, which help hold onto the spring mechanisms, as these are breaking off and the windows are becoming "sprung." PLEASE CALL OR EMAIL ME. I am attaching a photo of one of the window stickers with model numbers. Meanwhile I will cite some of the data here (from a different size window, but same mechanism--the stickers have fallen off of some of the other windows):

Manufacturer code: MTL-4
Series: 180/280/380
ANSI/AAMA 101-88
MST: 8054/10550.

Also, which of all these numbers is the actual model or series number? I would HUGELY appreciate any help you can give me.

User submitted a photo of a sticker on a window.
13 Replies
Tom from SWISCO
May 23, 2013 10:07 am
Thanks for posting! I'd be happy to help you with this project, but unfortunately we will be unable to replace the sash. MI is a manufacturer, so I recommend contacting them directly.

We may be able to replace the plastic catches, though. Could I see a few pictures of them removed from the window and with dimensions? That will help us determine what can work as a replacement.
Quick Learner from Pittsburgh
Jun 23, 2013 10:45 pm
Well, I finally got some photos of the tabs close-up. I'll describe them in order as attached here:

First, a broken tab on top of the lower sash. These are what I want to replace.

Second, an un-broken tab on top of the lower sash. Even there you can see they are somewhat bent upward from strain.

Third, a close-up of one of the plastic catches (an unbroken one).

And fourth, just a top measurement on another (unbroken) one that shows its overall length across the top to be 1-1/32, so I am wondering if your {1/2" Top Sash Clip, Pennco, Product Code: 18-061} item might work for me?

I'd be willing to try a pair to see if they work...??? Thanks so much!
User submitted a photo of window hardware.
User submitted photos of window hardware.
Tom from SWISCO
Jun 27, 2013 9:58 am
Ah, these pictures are perfect. check out our 18-093 Capitol top sash guide and let me know if this is a match.
Home Owner from Duluth GA 30096
Dec 29, 2014 9:28 pm
I need replacement my window about 18 years old, but I don't know , please look my pic below
Contractor from Palmetto, fl
Jun 25, 2016 9:45 pm
I'm looking for a replacement slider right side door. The glass shattered in place by itself and to have a glass company replace the glass is very expensive. I was told I can get a replacement door all intact to match for a fraction of the cost. Can you please provide me with some assistance. I can get the sticker on the frame if I know I can get a full door.
Quick Learner
Mar 6, 2019 6:09 pm
How do you determine the proper weight when replacing the constant force coil window balance?
Paul from SWISCO
Mar 7, 2019 8:42 am

If there is not a stamping on the balance that matches up with our stamping system, then you would need to remove the sash and weigh it on a scale. From there, you would visit any of our balance product pages. Below each product description, you will see a sash weight chart. Go with the stamp option that best fits the weight of your sash. 

Quick Learner from Fredericksburg
Jul 10, 2023 10:17 pm

I have a few windows and screens at my new rental these windows and screens need to be replaced

IMG_3730 IMG_3729 IMG_3726 IMG_3728 IMG_3724
5 user uploaded images
Tom from SWISCO
Jul 11, 2023 3:29 pm

Unfortunately, we don't sell replacement window screens of any kind. My suggestion is to contact a local hardware store that provides this service, or even the original maker of the window.

Contractor from Woodbine Md
Sep 15, 2023 9:24 am
I need 2 of these. Picture attached.
1 user uploaded images
Tom from SWISCO
Sep 19, 2023 10:20 am

I'm afraid I don't recognize this part. Can you tell me what this part does? Can you also tell me its dimensions? Finally, knowing who made the window may also be helpful.

I can't guarantee that we can get this for you but I will definitely try my best!

Home Owner from Virginia
Sep 27, 2023 8:44 am
Trying to identify and locate replacements for these integral window safety stops. Not even sure of the correct terminology. Appreciate any help.
1 user uploaded images
Tom from SWISCO
Sep 27, 2023 12:24 pm

Hello! These are generally called vent stops. We sell a small few handful of different styles, which you can see here, but unfortunately none of them match the design you show here. Ours won't be able to mount on your window like the original.

My suggestion is to contact the original window maker to see if they can provide you with this exact style.

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