Extension Spring (8mm OD, 6.8kg Max Load, 80-120mm Length)

This extension spring is commonly used with synthetic cable in order to retain tension where the cable path causes slight variances in the amount of slack in the line.  The spring has an overall length of 80mm at rest, but can be stretched 40mm for an overall length of 120mm.  The loop ends are just shy of 6mm so they can be snugly pressed over a 6mm diameter shaft or tube but they can also be slipped over a smaller diameter post such as an M4 screw.  The spring is made from spring-tempered steel to retain its rate and shape over thousands of cycles.