Time for an upgrade.
In the spirit of “going big” with Ultra4 racing, we’re very excited to release our all new 2-1/4″ threaded Aluminum Filler Cap & Steel Bung. This MASSIVE cap makes gear inspection a breeze, and filling your axle housing that much easier. Details over at http://www.spidertrax.com/Filler-Cap-2-1-4-Thread .