triple paper Everlasting Endless Pencil, Replaceable Graphite Nib Triangular Grip Pencil Pencil  (Set of 1, Blue)

Ergonomic design for an easy grip, 1. The comprehensive wear of this product is about 0.005mm when writing 1 meter, the loss is about 0.0062 cubic millimeters, the writable volume is about 99.011 cubic millimeters, and the theoretical writing is about 15900 meters. 2.Wooden pencil wears 1.8mm for 1 meter (international GB/T26704-2011). The theoretical writing length of this product is 100 meters. The theoretical writing length of this product is 159 times that of a wooden pencil.