SPEC® Constant Force Springs are a special type of extension spring, made from 301 stainless steel with a plain finish. The spiral construction allows for near constant rate of tension over the working extension, which is why this spring is sometimes known as constant tension spring. The constant tension provided by a constant force spring makes them a great candidate to provide a counterbalance for a product.

Mounting is generally achieved with a drum tightly fitted to the ID of the spring. The hole in the free end allows for easy mounting to your application. Additional flexibility in load is achieved with tandem or back-to-back configurations using more than one constant force spring. Be sure to keep 1.5 coils of material coiled at full extension.