Iso | 2768-mk-e

| Nominal Range (mm) | Straightness / Flatness (± mm) | Perpendicularity (± mm) | |--------------------|--------------------------------|-------------------------| | ≤10 | 0.05 | 0.1 | | >10 to 30 | 0.1 | 0.2 | | >30 to 100 | 0.2 | 0.3 | | >100 to 300 | 0.3 | 0.4 | | >300 to 1000 | 0.4 | 0.5 | | >1000 to 3000 | 0.5 | 0.6 |

A 200 mm long machined surface without a flatness callout → allowed flatness deviation = 0.3 mm. iso 2768-mk-e

| Class | Name | Precision | Typical Use | |-------|-------------|-----------------|----------------------------| | H | High | Tight | Precision engineering | | | Medium | Standard | General machining | | L | Low | Loose | Non-critical assemblies | | Nominal Range (mm) | Straightness / Flatness