Stainless tension spring. Made of 304 stainless steel, stainless, sturdy, weatherproof, optimal for outdoor use. Elasticity. Attachment to sail corners for strong permanent elastic tension and protection against extreme wind forces. Width of applications. Suitable for different types of sails (triangle, square, rectangle). Parameters Package: 6 x springs Material: 304 stainless steel Size: 11.5cmx3mm Compressed length: 5cm Weight: 62g 38kg. Suggestion for use: Always allow sufficient space between the corner of the sail and the attachment point: for the elements of tension (carabiner, turnbuckle, etc.) and permanently elastic tension elements (tension strap, tension springs). The protective sail must always be under permanent tension. Specification of the extension spring: particularly short with a basic length of 11.5 cm. high spring force 38kg Stainless spring steel