This is the Hard Aluminum 48P 37T Pro Pinion Gear from Robinson Racing.
FEATURES:
Hard Aluminum Construction
Black in Color
37 Tooth
48 Pitch
INCLUDES:
One 48P 37T Pinion Gear
One 3x3mm Set Screw
REQUIRES:
Installation on the Motor Shaft
SPECS:
Outer Diameter: 21.65mm (0.85")
Inner Diameter: 3.15mm (0.12")