The Kurutoga Has A Core Rotation Mechanism That Continually Rotates The Pencil Lead As You Write. A Spring-Loaded Clutch Twists The Lead Incrementally Every Time You Lift The Pencil From The Paper. This Allows A Uniform Wearing Of The Lead So That It Always Remains Pointed. This Is Great For Students! It Gives You An Amazingly Thin Line. In Effect, You Use Only 50% Of The Lead Area That You Were Previously Using With Your Old Mechanical Pencil. In Addition, This New Kurutoga Is Equipped With A Pipe Slide System.The Lead Is Difficult To Break As You Write, Due To The Innovative Mechanism. When The Core Is Reduced, The Pipe Gets Shorter At The Same Time. The Guide Pipe Protects The Entire Length Of The Lead. Because There'S No Lead Breakage, Your Papers Remain Clean Without Smudges From Broken Lead Dust.