21" Series 351 Channel Balance

Product Code: S351-21

21" Series 351 Channel Balance
Quantity Price
1-11 $9.59
12-49 $8.63
50-99 $8.15
100-249 $7.67
250+ $7.19
Please Note: Bulk pricing applies only to purchases of the same option
Product Description
This is a Series 351 channel balance for non-tilt windows. It moderates the operation of your window sash using a specifically calibrated spring and pulley system that allows the window to stay open when raised.
  • This balance has a 21" long metal channel. When determining the length, do not include the attached fittings. Only measure the metal channel.
  • Comes fully assembled with the 19-002 top and 15-002 (1" deep) bottom fittings and will be ready to install out of the box.
  • The strength you need should be indicated as a stamp or imprint on your old metal channel. If you do not have a stamp, or cannot match it up to our options, weigh your sash on a scale and refer to the chart below.
  • The width of the metal channel measures 9/16" but is considered 1/2" in the trade.
  • Can work for either the left or right side of the window interchangeably.

  • Stamp Option Sash Weight Range
    2010 5 to 8 lbs
    2020 8 to 12 lbs
    2030 12 to 15 lbs
    2040 15 to 23 lbs
    2050 23 to 27 lbs
    2060 27 to 30 lbs
    *This information is based on 2 balances per sash. Balances are designed assuming friction in the jamb weather-strip will carry a portion of the sash weight. Suggested sash weights are approximate.
Good Idea!
Balances are sold individually, however, it is a good idea to replace both window balances at the same time. Pairing a new balance with an old one would cause the new balance to wear out faster.
Helpful Tip!
The stamp option represents the strength of the channel balance. Locate the stamp on your channel balance. If your stamp does not match any of the stamp options available or you are unsure of which stamp option you should choose: ask our experts for help.
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Customer Questions & Answers
Discussion # Of Replies Last Post Date
Help with identifying a channel balanceThis discussion includes image(s). 2 Nov 14, 2022
21 inch metal frame by five inch wide. Came out of a western insulated glass aluminum frame from approximately 1980 to 85This discussion includes image(s). 2 Jun 23, 2022
Numbers 2030. Length 21 inchesThis discussion includes image(s). 2 Jan 19, 2022
Searching for 20 5 fBSTThis discussion includes image(s). 2 Dec 26, 2021
ReplacementThis discussion includes image(s). 2 Oct 9, 2021
Window balancerThis discussion includes image(s). 2 Sep 23, 2021
Channel Balance IdentificationThis discussion includes image(s). 4 Sep 12, 2021
Help identifying right piece 3 Aug 12, 2021
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