The 4Runner 5th Gen ALUMINUM Rear Link Kit starts with our 2.0" outer diameter, aerospace grade 7075 Aluminum lower links and 1.5" OD upper links. The aluminum links are out-fitted with time-tested Rock Krawler brand Krawler Joints with a 1.25" thread on the lowers and 7/8" thread on the uppers with matching jam nuts. These are the same joints shipped in nearly every Rock Krawler lift kit so you know they stand up to the test of time and abuse...not to mention there are millions of them on the streets. Each link is threaded with both a Right Hand thread and a Left Hand thread at opposite ends so it is easy to adjust the length for fine tuning. We've also included wrench flats on each end of the aluminum link so you can easily tighten your jam nuts without marring the aluminum. The real advantage of our aluminum link suspensions is the weight savings. Each link only weighs a few pounds versus steel links which can be dozens of pounds. This weight savings means better fuel mileage, less wear and tear on your vehicle and it's components, easier install and less maintenance. Aluminum also is naturally rust resistant so you don't have to continually paint them if you scratch them plus aluminum's natural shininess adds so much curb appeal to your vehicle. A big benefit to 7075 aluminum also is that the material has a memory and will return to its natural straight shape after taking a big hit. While steel control arms will dent and stay bent, 7075 aluminum will remain straight for years and years of constant beating. This is most important on lower links that really take the hits on rocks. Springs, shocks, limit straps, sway bar extensions, and extended brake lines are not included in this kit and will be needed. TWO UPPER LINKS, TWO LOWER LINKS, AND TRACK BAR ARE INCLUDED IN THIS KIT. TRACK BAR ONLY USED IN VEHICLES WITH A LIFT, NOT STOCK HEIGHT. Included in this Kit: 2 - RH, 2 - LH - 1.25" -12 tpi x 9/16" hole Rock Krawler Joints 2 - RH, 2 - LH - 1.25" -12 tpi Jam Nuts 2 - RH, 2 - LH - 7/8" -14 tpi x 12mm hole Rock Krawler Joints 3 - RH, 3 - LH - 7/8" -14 tpi Jam Nuts 1 - RH, 1 - LH - 7/8" -14 tpi JMX Pro Rod Ends 4 - 7/8" x 14 mm High Misalignment Spacers 2 - 2.0" OD 7075-T6 Polished Aluminum Lower Links 2 - 1.5" OD 7075-T6 Polished Aluminum Upper Links 1 - 1.5" OD 7075-T6 Polished Trackbar Link 4 - 9/16" bolts, washers, and lock nuts