Low ash paper hardened (max 0.02%), as an intermediate solution between quantatitive ash free paper (max 0.002%) and qualitative paper low ash (max 0.06%) for non critical quantative works. Recommended for thin precipitates, such as barium, lead, zinc or nickel sulfate, barium fluoride or barium hydroxide. High wet resistance. Surface weight 80 g/m², pore 7 - 9 ?m, thickness 290 ?m. Available in flat disks (packed in 100 disks bag foiled packaging, with no carton box), or folded (in a carton box). Equivalent to: Whatman 50