1. Dimensional Specifications

These are the measurements that define the size, shape, and geometry of a part.

Overall Dimensions: Includes length, width, height, and diameter (for round parts). E.g., "Part length: 150mm ± 0.05mm."

Tolerance: The allowable variation from the specified dimensions. Tight tolerances ensure high precision. E.g., "Tolerance: ±0.01mm" or "Tight tolerance: ±0.005mm."

Surface Finish: The texture or smoothness of a surface, usually indicated in terms of Ra (Roughness Average) values. E.g., "Surface finish: Ra 0.8 μm."

Flatness: The degree to which a surface is flat, typically measured using a height gauge or CMM (Coordinate Measuring Machine). E.g., "Flatness: 0.02mm over a 100mm span."

Roundness: How circular a hole or part is, usually measured as a deviation from perfect roundness. E.g., "Roundness: 0.005mm."