Certainteed 405L 3/4 inch wide long tongue coil spring for vinyl windows.
The long tongue coil spring is attached above the short tongue and screwed to the pivot lock brake shoe, when making a tandem window balance assembly

Application: Used make a tandem balance
Spring Width: 3/4 inch
Spring Type: Long Tongue ( when using 2 springs in tandem)
Available in 6 different weights.
Priced and sold each, no screw

Number stamped on single coil spring:
405-L 5 pounds
406-L 6 pounds
407-L 7 pounds
408-L 8 pounds
409-L 9 pounds
410-L 10 pounds

NOTE: there are many variations - If not sure, send us pictures or sample