Size - size drawings 30 x 18 mm. Made of high -quality metal materials, zinc alloy. Packaging - You receive 150 sets of metal twisting. The tools you provide that your fastener is well installed, so that you can rest that your canvas remain in place. fastener - this set of 150 - level twisting fasteners, holes and threads provides a safe way to install canvas or other materials on the . The twisting design - the innovative twisting mechanism is closely grasping the material without any tools, which is convenient for two parts to fasten and adjustable tension. Twist-lock fastening parts are designed to provide safe and close locks; this ensures that your fastener is in place without accidental loosening, thereby protecting your marine canvas. Multi-purpose - very suitable for tents, waterproof cloths, etc. These fasteners can be installed on wood, metal, hard plastic and composite materials. In addition to fixed canvas holes, these multifunctional canvas fasteners can also be used for waterproof fabric fastening fasteners and twisting screws to fasten fasteners; its multifunctional character makes it a precious supplement to any toolkit package. Colour:As Shown Material:alloy steel Package Contents: 3set x twist lock fasteners 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.