To understand the "Extra Quality" designation, one must first understand the base standard.
, which is thicker, smoother, and more durable than standard 70 GSM office paper. Archival Properties : These papers are typically multikey 1822 extra quality
| Feature | Specification | | :--- | :--- | | | DIN 1822 | | Material | High-Carbon Spring Steel (Special Grade) | | Hardness | Approx. 700 HV (Vickers) / 60 HRC | | Tolerance | Precision Ground (Tighter than standard ISO tolerances) | | Surface | Smooth ground, polished | | Primary Use | Gap measurement, clearance checking, shimming | To understand the "Extra Quality" designation, one must