Severe service aluminum through-bolt case (4.000" bore), 40-spline lightweight steel spool, aluminum caps, MW steel 1350 series 35-spline pinion yoke (can be upgraded to 1480), angular contact ball / ball bearing pinion support, 1/2" ring gear bolts, your choice of large pinion 10" 9310 pro gear.
 
Manufacturer: Mark Williams Enterprises, Inc.