0-RRP1339 Robinson Racing Products 48 Pitch Hard Coated Aluminum Pinion Gear, 39T <p><font color="00ff66" size="2" face="Arial, Helvetica, sans-serif">The "Pro" Pinions are precision machined from aircraft aluminum, lightened and then they're coated twice with a super hard, black anodize. Recommended for onroad, but they can be run off road. Pinions (14 thru 35) stamped with tooth number. 1/8 inch bore. One 5-40 set screw included. </font></p>
<p><font color="00ff66" size="2" face="Arial, Helvetica, sans-serif">Outer Diameter: 21.65mm (0.85")<br />
Inner Diameter: 3.15mm (0.12")
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