Headless screws, designed to be fully housed in the material or component in which it is screwed. The drive takes place through a hexagonal key (brugola) inserted in the recess at the top end. The size is M8x20mm, which indicates a nominal diameter of the 8 mm thread and a length of 20 mm. The distinctive element is the conical tip, which concentrates the clamping force at a specific point, ensuring a precise fixing or locking, often used to prevent rotation or relative movement between two components, such as a shaft and a hub. Specifications Main Techniques Type: Headless Screw (Grano) Reference Regulation: DIN 914 / ISO 4027 Thread: Metric ISO large-step (M8) Diameter Name: $8 \text{ mm}$ Length: $20 \text{ mm}$ Type of Extremity (Punta): Conical (Conical plug) Type of Incasso: Esagono Incassato (Brugola) Typical Material: Alloy steel (45H hardness class) or Stainless steel (A2/A4) Threading step: $1.25 \text{ mm}$ (Standard M8) Primary Application: Fixing and radial locking to avoid rotation