window balance : SWISCO.com

Tom from SWISCO

Mar 29, 2019 2:27 pm

Based on the photos you submitted, it looks like you have either the S351 or S390 balance.

The difference between the S351 and S390 balances lies in the shoe.

The series 351 channel balance has the 15-002 shoe while the series 390 channel balance has the 15-001 shoe. The 15-001 shoe is 1/8" larger from front to back.

We hope you find this helpful. Please let us know if you have other questions.

Comparison of the S351 and S390 balance shoes.

8 Replies

Quick Learner from daytona beach ,fl

Mar 29, 2019 3:09 pm

window balance 1/2" channel,bottom 1" x 1& 1/32",stamped DS26 37,also BSI , channel measures 27" without (metal only)

5 user uploaded images

Quick Learner from daytona beach ,fl

Mar 30, 2019 7:03 am

The shoe does measure 1"x1&1/8" so it is a 390 balance,is that right? Does the no.37 stamped on the channel shown in the last picture indicate the weight?(ds26 37)

Tom from SWISCO

Mar 30, 2019 12:46 pm

Yes, typically that number is the sash weight. With that in mind, and referencing the chart on our S390-28 store page, you'd want our 2770 option.

If your shoe is 1-1/8" deep then the 15-001 is correct.

Quick Learner from daytona beach ,fl

Mar 30, 2019 8:11 pm

Please reference previous post stating the channel length of 27".I believe the chart for S390 with a length of 27" would call for 2760 option- is this correct?

Tom from SWISCO

Apr 1, 2019 8:17 am

Oh jeeze, sorry about that. I misread that. If your balance is 27" long, then you want our 2670 stamp instead. This carries 36 through 39 pounds.

You may want to weigh your sash on a scale just to be 100% sure that it's 37 pounds. If it isn't, get back to me and we can figure something out.

Quick Learner from daytona beach ,fl

Apr 1, 2019 2:27 pm

Here are some additional pics. Please verify this is an S390-27. I will weigh the sash and report back to finalize my order this afternoon.

Sash weight is 36.6 lbs. Please verify part number.

Thanks, Bob C.

5 user uploaded images

Tom from SWISCO

Apr 2, 2019 8:47 am

Thanks for getting back to us! I agree, our S390-27 looks like a good choice. If your sash weight is 36.6 pounds, then our 2670 option should work great.