Robinson Racing Products 48 Pitch Hard Coated Aluminum Pinion Gear, 37T 48P, 37T, 1/8in bore pinion gear.
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Robinson Racing Products 48 Pitch Hard Coated Aluminum Pinion Gear, 37T Part# 0-RRPC1337
This pinion gear bag includes one 48P 37T Pinion Gear, and one 3x3mm Set Screw.
Outer Diameter: 21.65mm (0.85") Inner Diameter: 3.15mm (0.12")