7.5 lb Constant Force Coil Spring, 1/2" for 1-1/4" Window Pocket

Coil Spring 1/2" Constant Force, 7.5 lb for 1-1/4" Window Pocket

This universal constant force coil spring is designed for use with single or double hung sliding windows that require a 1-1/4" (31.8mm) pocket width. Specifically engineered to provide balanced, smooth sash movement, it supports up to 7.5 pounds (3.4kg) per spring, making it suitable for a wide range of residential window applications. The coil thickness is 1/2" (12.7mm), and the spring is compatible with various sash weights when combined with matching coils. Numbers indicating the weight capacity are stamped on the end of the coil, though they can sometimes be difficult to see.

This product is sold as a coil only and can be used in conjunction with other hardware components such as support covers, brake shoes, and pivots, which are sold separately. Multiple coils can be stacked as needed to precisely match your window's sash weight, with additional weight capacities (3.5, 4.5, 5.5, 6.5, 7.5, and 9 pounds) available to meet other requirements.

Technical Information

• Pocket Width: 1-1/4" (31.8mm)
• Coil Thickness: 1/2" (12.7mm)
• Weight Capacity: 7.5 lbs (3.4kg) per spring
• Manufacturer: Amesbury Truth Hardware

Notes

• Works for both single and double hung sliding windows.
• Numbers indicating spring capacity are located on the end of the coil, though visibility may vary.
• Coils, support covers, brake shoes, and pivots are available separately to assemble a complete window balance system.

Sold individually as a replacement coil spring. Please measure your existing hardware carefully—including pocket width, coil thickness, and weight rating—to ensure correct fit before ordering. Always confirm all measurements to match your original balance assembly for proper replacement.