Revolution Gear and Axle Discovery Series D44, 4340 Chromoly HD Front Axle Kit for 07-18 Jeep Wrangler JK Rubicon, 30 spline kit Only works with factory locker. This Revolution Front Axle Kits comes with 2 4340 Chromoly inner axles, 2 4340 Chromoly outer stub axles, 2 HD Larger 1350 Style Chromoly needle bearing U-Joints and 8 Full Circle Snap rings to hold it all together. Revolution uses the large 1350 Style U-Joint for all of our Jeep applications. Using the substantially larger 1350 Style U-Joint provides a substantial increase in strength over the smaller 5-760X U-Joint and allows extra clearance for tighter turning. All Discovery Series Axles are backed by a 10 Year Warranty covering manufacturing defects and axle breakage, bent axles and twisted splines. This warranty is non-transferable. U-Joints are only covered under warranty for 1 Year (Other than Revolution Gear HD Chromoly U-Joints). Parts subject to normal wear are not covered under warranty; this includes bearings and seals.