This is a 1.5mm Allen Wrench used to tighten and loosen our 550 pinion gear set screws.
Typhon - Upgrade pinion gear now motor not fitting
Power Wheels Stage V Hardened Steel First Gear with Ball Bearings
Tekno RC M5 Hardened Steel Mod1 Pinion Gear w/5mm Bore (26T) [TKR4186] - AMain Hobbies
Jeanoko 3-Piece Replacement Accessory Engine Pinion Gear Steel Professional Pinion Gear with Hex Wrench for Outdoor Activities (23T) : Toys & Games
JEGS 555-65262 Mag Lug Nuts, Medium Open-End [1/2 in.-20 RH, Chrome] - JEGS
550 Motor Pinions - REV Robotics
Typhon - Upgrade pinion gear now motor not fitting
Power Wheel, Kid Trax, and other brands of Modification Parts
Banebots P61 Gearbox: 1.5 inch Shaft, RS-540/550 Mount, 26:1 (No Grease) - RobotShop
23-T Pinion Gear (48-pitch), Set Screw
20 DP Motor Pinions (16 Choices) - VEX Robotics
Motor Shaft Gear Adapter, 3.175mm to 5mm Rust Proof Pinion Reducer Sleeve Adapter for RC Motor 3650 550 Pinion Gears : Toys & Games
RJX Motor Gear Puller, Motor Pinion Gear Puller Remover Tools Set RC Hobby Model Motor Pinion Parts