so that the internal structure of the servo can absorb heat and smooth operation

Since they are made by Traxxas

Precision-Machined Rotating Wheels to Assure Perfect Balance Easily

75C continuous discharge rating

Powerhobby Hardened Steel 30T Mod1 8mm Pinion Gear MOD 1 Speed Run / Drag Racing 1/32 Slot Car so that the internal structurePowerhobby Hardened Steel 30T Mod1 8mm Pinion Gear with 2 Grub Screws Description Fine tune your high power RC vehicles gearing with a Powerhobby Hardened Steel Mod 1 Pinion Gear. Designed for motors with an 8mm output shaft, these heavy duty pinions provide the strength and durability required for large scale RC vehicles, speed run cars, drag racing builds, and other high performance applications. Each pinion features two set screw holes and includes