Millguard window ballancer

Hello,

We'd be happy to help but the bottom fitting is only partially shown in your photos. It would help to see an unobstructed photo of that part as well to narrow down your options.

Your stamp codes are also a bit unusual since you mentioned that these balances are for one window, which should have the same stamp codes. It is possible that someone replaced one of the assemblies with a balance that they had on hand rather than an exact replacement. To determine the correct spring strength for your replacement balances, we would need you to confirm the exact weight of the window sash that the balances support.

A 26DS45 stamp would normally indicate that the sash would weigh 45 pounds, while the 26-4 stamp balances would support a much lighter sash. Both balances must be calibrated to support the exact weight of the sash to prevent damage to the hardware or the window itself. Thank you! 

Thanks for getting back to us. With this combination of attachments, you could have either the S380-27 or S385-27 channel balance. You’ll need to measure as shown below. The Series 380 has a 1" bottom attachment, and the Series 385 has a 1-3/32" attachment. 

The 2640 spring strength options for these balances will support a sash between 19-26 lbs. I would strongly recommend weighing your sash to confirm that it falls within the supported range. Thank you and let us know if you have any other questions or concerns.

Comparison of the S378, S380 and S385 balance shoes.