This is a 6.0 mm double‑ended hex key (Allen key) designed for engaging metric internal hex (socket) screws and bolts. The tool is a double‑ended L‑shaped hex key with a long arm for reach and a short arm for increased torque, both ends sized at 6.0 mm so it can be used interchangeably depending on access and leverage requirements.

The key is manufactured from chrome‑vanadium (Cr‑V) tool steel produced to EN ISO 4957 tool‑steel specifications and is heat treated to give the core strength required for repeated torqueing without permanent deformation. It is supplied with a black oxide finish to give basic corrosion resistance and reduce surface glare; the finish also helps prevent fretting where the key contacts the fastener recess. The drive type is internal hex (Allen), matched to standard metric hexagon socket screw dimensions used by ISO/DIN (for example ISO 4762 / DIN 912), ensuring reliable fit with common socket head cap screws. Thread type is not applicable for this hand tool.

Typical uses for a 6.0 mm double‑ended hex key include maintenance and assembly tasks on machinery, automotive and motorcycle repairs, bicycle servicing, plant and factory maintenance, and furniture or equipment assembly that uses metric hex socket fasteners. The long arm gives access into recessed or awkward locations while the short arm provides increased torque for tightening or loosening stubborn screws, making it a practical choice for engineers, maintenance technicians and tradespeople.

Key benefits are its material strength and durability from Cr‑V tool steel and heat treatment, the convenience of two working lengths in a single tool, and compatibility with widely used ISO/DIN metric socket screw sizes. The black oxide finish helps resist surface corrosion in workshop environments while avoiding the bulk or peeling risk of thicker platings.

Duchy Fasteners stocks this item individually and in small multi‑packs, and holds a full range of metric hex keys across standard sizes for bulk and trade requirements. Please contact us for current stock levels and pack options.