Associated Electrics 48 Pitch Spur Gear, 75T: B4/T4 48P, 75T spur gear.
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Associated Electrics 48 Pitch Spur Gear, 75T: B4/T4 Part# 0-ASC9650
Outer Diameter: 40.7mm (1.6") Inner Diameter: 4.75mm (0.19") Width: 5.25mm (0.21")