... hole, square, triangle, diamond, hexagonal, cross, slotted Opening type: round, square, triangle, diamond, star etc. Material: iron sheet ... Patterns including: round, rectangular, square, triangle, diamond, hexagonal, cross, slotted and special patterns to ... degree), rectangular, elliptical, square, triangle, diamond, hexagonal, cross, slotted, star, plum blossom, other special patterns.Sheet ...