Professional-quality technical drawing pencil. The diameter of the HB lead is identifi ed by the colour bands: Yellow 0.3mm, Red 0.5mm, Blue 0.7mm, Green 0.9mm. Brass Morse key. Metal ribbed grip. Equipped with gradation-indicator at top of metal structured collar. Reinforced lead: 20% more solid than traditional lead. Extreme-density lead for clean and detailed tracing. Includes a tip- cleaner for use in event of obstruction.