perforated metal in steel plate,stainless steel plate,aluminum plate,size according requirment,Material: S.S.; Hot Dip Gal. ... so on the stainless steel, aluminum sheet, cold hot steel plate, copper plate, PVC board membrane, passes:Long hole, square edged orifice, ... absorption board, may use in the building ceiling, the wall plate absorption material, may use in the building staircase, the balcony ...