TIBO/BLOKKER manufactures and supplies potato grading screens, onion grading boards, bar screens with aluminium bars, flower-bulb grading boards, etc. All the grading boards and grading screens can be supplied in any desired length and breadth. The material selected may be aluminium, stainless steel and steel. The grading boards can be supplied with or without a border strip in all sizes or versions, with or without magnetic strips. The plates are coated with sheet rubber and have round holes. Grading boards of perforated steel can also be supplied.