• Brand = Staedtler
• Model Number = 200-HB ST
• Colour = Blue
• Material = Plastic
• Pack of 12
• Manufacturer Part Number = 200-HB
• Manufacturer = Staedtler
• Country of Origin = India

The 0.7mm leads are thicker, which is better for people who tend to press hard on the pencil when writing. 

For drawing,use 0.5mm leads, because they're more precise than the 0.7mm leads. The softest lead that is available to fit in a pencil is 120 /a 3 0.7 mm.

Pencil lead is made of a mixture of graphite and clay. The graphite is the part that makes the dark mark on the paper.

The clay is there because graphite on its own is far too soft and crumbly to write or draw with.

Thin leads for mechanical pencils are similar, but with a polymer or resin taking the place of the clay.