16" Series 390 options

A handy person from Merritt Island, FL says:
My window balance looks like this 16" Series 390, but none of the options look like what is stamped on the existing unit. Mine is stamped 15 5 NK BSI.
User submitted a photo of a window balance.
Profile picture of Tom
Tom from SWISCO responded:
A "15 5" stamp usually corresponds to our 1550 option, but you can always weigh your sash to confirm.
A handy person from Merritt Island says:
The window weighs about 22 pounds.
Profile picture of Tom
Tom from SWISCO responded:
Ah, I see. In that case, the 1550 option will not work. Did you ever find that your old balances were too weak? Your old stamp of "15 5" should not have been able to hold up 22 pounds that well.

We can custom make an S390-16 channel balance with a 1565 option, if you'd like. Two balances with this option can hold a sash weight of 20 through 23 pounds, which encompasses your own sash weight. If you're interested, please let me know how many you need and I can send you a custom order form and price quote.
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