Hobby-Ace 520 Drive Gear Bearings for Parrot AR Drone Quadcopter 2.0 and 1 (8PCS) Suitable for Parrot AR Drone 1.0 2.0 quadcopter. Shielded and sealed design, better dust-proof. More fluent, better dust-proof and durable.Same size with the original one, easy installation. Remove the propeller and main gear firstly, and then use this new sealed gearing to replace the old one, try to install slightly and carefully.