RS PRO HSS Twist Drill Bit, 4mm Diameter, 250 mm Overall

This Metric Extra Length Twist Drill Bit from our own RS PRO brand is an industrial grade drill bit in super high speed HSS steel for accurate and easy drilling of all metals, special and hardened steels and alloys.

• Base material: High Speed Steel
• Point angle: 118°
• Straight cylindrical shank
• Right hand cutting
• Rolled spiral flute with ground point, vapour – plated
• Two-cutter, cylindrical, two flutes

• Suitable for wood, plastic/composites, mild and cast steel (alloy and non-alloy), grey cast iron, tempered castings, sintered materials, graphite and nodular iron

An acronym for High-speed steel, HSS is generally the go-to type of steel needed for drill bits due to their excellent heat resistance at high speeds. As a standard drill can spin upwards of around 500 - 700rpm, the friction can cause a substantial build-up of heat. Something which would not be wanted when working with wood and plastic.

RS PRO is our own brand range and brings you a wide range of high-quality, great value products offering you more choice. Trusted by engineers all over the world, every part of every RS PRO product has been rigorously tested against demanding industry standards; they’re only given the RS PRO seal of approval if we’re confident of their exceptional quality, which means you can be confident too.

BS 328; ISO 3292

HSS Long & Extra Long Series

These HSS straight shank, right hand cutting long series twist drills are capable of drilling up to 10x the drill diameter before the flute needs to be cleared, to avoid fouling. They are made to BS328/DIN340 RN and ISO standards, and are recommended for use with steel and cast iron.