The mat of the present invention includes a main body integrally formed by a plastic material. The main body at least has a first surface and a second surface adjacent to the first face. The first face and the second face have different surface physical characteristics. The first surface and the second surface are shaped into a third surface and a fourth surface respectively. The third surface and the fourth surface have a substantially same surface physical characteristic. An angle between the third surface and the fourth surface outside the main body is a specific value.