These protection covers are made by high quality raw material by mixed with POM plastic, aluminum powder and fiber. They are designed to offer full protection to the engine cover / gear box case / crank case / clucth case / pulse case (protection parts may be various depending on the specific bike model). The high quality mixture material makes the protection covers slide to the ground when crash with no crack like regular protection gears. They will not crack even meeting motorcycle falling. The covers could even stand for maximum 700 centigrade degree. All mounting bolts are included. Very easy to handle. All mounting hard wares included. No extra modifications jobs needed. The covers come with detail manual and instruction. Covers come with manual. Please follow the included installation instruction to install the covers. All necessary parts are included. Plastic + aluminum powder + fiber. Engine cover x 1 set, bolts are included (same to the photos).