21" Series 380 Channel Balance

Product Code: S380-21

21" Series 380 Channel Balance
Main product image of the S380-21 21" Series 380 Channel Balance
19-005 top shoe attachment.
15-005 bottom shoe attachment.
How to identify a replacement channel balance
How to Replace a Non-Tilt Channel Balance
How to Repair a Jammed Window
Quantity Price
1-11 $8.75
12-49 $7.87
50-99 $7.44
100-249 $7.00
250+ $6.56
Please Note: Bulk pricing applies only to purchases of the same option
add $0.75
Product Description
This is a Series 380 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 19-005 top and 15-005 (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 lb
2020 8 to 12 lb
2030 12 to 15 lb
2040 15 to 23 lb
2050 23 to 27 lb
*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.
Customer Questions & Answers
Discussion # Of Replies Last Post Date
which balance to order?This discussion includes image(s). 2 Jul 24, 2020
Balance replacements This discussion includes image(s). 7 Jul 20, 2020
Help Identifying 21" Channel, Top and ShoeThis discussion includes image(s). 2 Jul 19, 2020
Window Balance SpringThis discussion includes image(s). 2 Jul 17, 2020
Channel Balance IDThis discussion includes image(s). 2 Jul 16, 2020
Need help for identifying channel balancesThis discussion includes image(s). 2 Jul 14, 2020
Searching for 86 20-3 IA5 CMC 2This discussion includes image(s). 4 May 14, 2020
Milgard Window 21" channel balancerThis discussion includes image(s). 10 Apr 21, 2020
Start a new discussion
Use this form to ask questions or to share your experiences regarding this product. Every discussion will be reviewed and answered by our experts.
(your email address will be kept private and is only used to inform you when a response has been made)