4" EXTENDER TRAIL III™ SERIES This 7/16 diameter is a popular runner for trail riding.? Woody’s offers the Extender Trail III™ line to replace the manufacturer’s stock runners.? The 4 of 60? turning carbide will give more positive cornering control.? Our guideline for consideration of these runners would be for sleds with up to 96 studs installed in the track 6" TRAIL BLAZER IV™ SERIES This ? diameter runner is designed for trail riders looking for performance in cornering, power and control. The turning carbide is 6 long with a 60? edge. The 1? front and rear carbide wear pads prevent premature runner wear. It is essential that the track be studded when using this runner. 8" EXECUTIVE™ SERIES A beefy ? diameter runner with lots of turning carbide for many forms of competition and experiended riders.? Performance trail riders are known to use this runner.? The 8 of 60? edged carbide translates into extreme turning power.? A 1-? carbide wear pad helps prevent premature runner wear