1. Super steel sheet springs. 2. The rigid spring increases the payload capacity. 3. Simple installation, no modification required. 4. Stamped steel parts (shackles / supports). Descriptions: This is a complete kit of steel sheet springs with tools needed to assemble and install. Specifications: Screw thread: M3 Fit for: D90 Colour:Black Material:metal Package Contents: 4*Leaf Springs 1*accessories kit Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.