Büchner funnel with sintered disc porosity 4, cap. 200 ml , Ø 65 mm, cone 29/32

Made of top quality 3.3 borosilicate glass. They should be used with a filtering flask with standard ground mouth reference FFK3. Each funnel has a sintered disc with a different porosity grade: 90-150 ?m (porosity 1), 40-90 ?m (porosity 2), 15-40 ?m (porosity 3), 5-15 ?m (porosity 4)