Dust Mask,PP Dust Respirator 1)15 years manufacturer 2)certificated by ISO9001,EN14683 3)Anti ... efficiency : 95% Pressure drop of inhale :< =2.5P(mm water) Pressure drop of inhale:< =1.5P(mm water) Dead room : 180cm3 Hindrance on ... ,160g,180g,200g,220g,240g Packing: a. 50pcs/inner box, 1,000pcs/ctnb. 50pcs/polybag, 2,000pcs/ctnc. 5pcs/polybag with ...