Leonardi tool for the removal of the Hollowgram crank arms from the spindle. The Cannondale version of this tool wears out over time, this version is higher quality and has a much easier thumb groove for insertion into the crank arm! Simply remove the bolt from the crank arm, thread in the nut with an 8mm wrench, thumb on the outer tool into the crank arm, and then back off the threaded insert with an 8mm allen wrench. Precision CNC'd. Made in Italy.