Goat skin: facial leather grain is semicircular arc, arc is arranged on 2 -- 4 needle pore, there are a lot of fine nap holes around, pore is arranged in fish-scale shape, feel is rich in extendibility; (2) sheep skin: the leather surface is smooth and clean, the leather board is thin, the pores are small and oblate, composed of a group of pores, row growth row, uniform color, the leather body is full, soft, and full of extensibility...