Filter paper circles Munktell grade 391 blue spot, 125 mm Ø

suitable for quantitative analysis, extremely low ash content (approx. 0.007 %), wet-strength, acid-washed, fine-grained precipitates such as brium sulphate, metastannic acid, cuprous oxide, very slow filtering, fine pores, very tight, very fine crystalline, filtration velocity 2500 s/10 ml, filtration time (Herzberg) 2500 s/100 ml | 25 ml/min., basis weight 84 g/m², typical pore size (retention range / recommended guide) 2-3 µm, 100 circles in a pack