Manufactured in the U.S. using only high-strength chromoly materials, RCV Performance Ultimate CV Axle set simply replaces your weak Nissan Patrol Y60 and Y61 axle shafts with a new high-strength design. The factory axles were designed with 31 splines at the differential, and neck down to 27 Spline at the CV creating a common failure point. This axle set upgrades the weak 27 splines at the CV to a 300M 30 spline race eliminating the need to neck down the shaft. Tests prove Ultimate CV Axles to be twice as strong as OEM shafts, and they’re just as tough at a straight angle as they are at extreme angles. Even if you have big tires and big power there are no worries. Ultimate CV Axles are low maintenance and operate with a smoothness you can feel – whether off road or on the street.