Quantitative Grade, Hardened
| Grade No. | Flowrate | Retention microns | Wet strength | Thickness, mm | Ash % | |
| 52 | General purpose hardened grade | Medium | 7 | High | 0.17 | 0.025 |
Quantitative Grade, Hardened
| Grade No. | Flowrate | Retention microns | Wet strength | Thickness, mm | Ash % | |
| 52 | General purpose hardened grade | Medium | 7 | High | 0.17 | 0.025 |