S152 coils for an 18 lbs. window

A home owner from Buffalo, NY says:
August 27, 2022
Need both coil balance springs for my window, ( S-152 )Cannot detect any numbers or letters on either one. The window weighs 18 Lbs. I assume the 9# coils will work? Thank you.
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Casey from SWISCO responded:
August 30, 2022

Hello,

I agree that as long as your original coil springs are an exact match to the S152 and your sash weighs exactly 18-pounds, then one S152-9 on each side of the window would provide the correct amount of strength. Thanks for posting! 
9 lb Series 152 Coil Balance
9 lb Series 152 Coil Balance
S152-9
$5.15
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