ISR Performance Pro Series Rear Upper Control Arm - 89-98 Nissan 240sx S13/S14IS RUCA NS134 PRO ISR Pro Series Rear Upper Control Arm Nissan 240sx 89 98 S13 S14 After Years of Success with the Basic Street Series Suspension arms ISR Performance has released a higher end line of suspension providing better control and overall performance. These are a great Arms for the street and track use. Pro Series Improvements Japanese Spherical Rod Bearings Larger Rod Ends Rod End Dust Boots Thicker Materials Add Bracing Same arms as used