... /MDF 4.Back:Zinc 5.Category:white/black/green board green board,chalk board,writing board1.Surface : Green painted steel sheet.2. Inner of ... the green board can be 7-layer strongs cardboard, Honeycomb board, MDF ... long-term trade relations with you on mutual benefit. Green board,chalk board,writing board BW-V1,2, 3,4~10