The solid carbide end mill with AlTiN coating, Z4 four-flute geometry and 35° helix is designed for precision milling on CNC machining centres, automatic machines and conventional machine tools. The dimensional configuration is d1= 16 mm L1= 45 mm L= 100 mm. Compared with a Z3 end mill, the four-flute version provides one additional cutting edge, higher edge support, smoother cutting continuity and improved surface finish, especially in contouring, shoulder milling, side milling and finishing of vertical walls. Chip evacuation must be managed with correct parameters because the higher number of flutes reduces chip space compared with tools with fewer flutes; for this reason Z4 geometry is particularly suitable on rigid machines, with accurate clamping systems and milling strategies where stability, dimensional precision and surface quality are the main requirements. The flat end cutting design enables end cutting, flat bottoms, light face milling and pockets with regular bottom geometry, while the peripheral cutting edges support shoulder milling, wall finishing, contouring and precision finishing passes. This configuration is useful in mechanical workshops, automotive production, precision engineering, mould making, industrial maintenance and quality-control departments when the workpiece requires reduced vibration, stable dimensions and improved finishing quality. The AlTiN coating is suitable for machining operations with high thermal load. The aluminium titanium nitride structure promotes the formation of a protective aluminium oxide barrier in the cutting zone, improving oxidation resistance and reducing abrasive and adhesive wear. It is suitable for alloy steels, structural steels, tool steels, stainless steels, cast irons and hardened steels, especially in high-speed milling, dry machining, near-dry machining or reduced-coolant applications. It is not the primary choice for aluminium and highly adhesive non-ferrous alloys, where polished geometries or dedicated coatings are usually preferable. For reliable results, it is important to use holders or collet chucks with low runout, check tool-system concentricity, avoid excessive overhang and set cutting speed, feed per tooth, radial engagement and axial depth according to material, machine power, coolant strategy and workpiece clamping. Correct parameter selection reduces vibration, form errors, dimensional deviations, premature wear and surface defects, improving tool life and process stability.