The quantitative or ashless filter papers are made with 100% high quality cotton linter fibres, which go through a severe chemical process. They have been washed out with a specific acid treatment and finally cleaned from impurities with demineralised water. This process allows reaching an ash content below 0.01%. Very slow filtration quantitative filter paper.

• Equivalent to Whatman grade 42
• Recommended for very slow filtration
• Weight: 84g/m²
• Thickness: 0.17mm
• Pore size: 2 - 4µm
• Filtration speed: 140s
• Supplied as plain discs