Quantitative Grade, Hardened Ashless
| Grade No. | Flowrate | Retention microns | Wet strength | Thickness, mm | Ash % | |
| 542 | Highly retentive for fine precipitates | Slow | 2.7 | High | 0.15 | 0.008 |
FILTER PAPER CIRCLES WHATMAN GRADE NO.542 24CM DIA BOX 100
Quantitative Grade, Hardened Ashless
| Grade No. | Flowrate | Retention microns | Wet strength | Thickness, mm | Ash % | |
| 542 | Highly retentive for fine precipitates | Slow | 2.7 | High | 0.15 | 0.008 |