The ARRMA Kraton 8S & Outcast 8S are 26 lbs. (12kg.Our replacement rear A-arms are designed with the backyard basher in mind and can handle some serious abuse and come back for more. RPM rear A-arms have a triple beam style construction designed to spread impact energy across all three beams. Each beam’s cross-section is a whopping 5/8” (15.8mm) tall x 3/8” (9.5mm) wide. These massive beams reduce unwanted flex during normal suspension movement, yet allow impact-absorption during those not-so-perfect landings and crashes. We also moved the inner cross brace away from the chassis, eliminating the droop stop entirely. While this may seem counter-intuitive, our test truck’s chassis was bent at the droop stops, clearly illustrating that extreme impacts were too much for the chassis plate to handle. After all, there’s nothing worse than a bent chassis. Made in the USA from our trademark blend of ultra durable materials, you can’t go wrong with RPM! Version Notes: RPM A-arms work perfectly with 8S versions of the Kraton & Outcast using ARRMA #330569 Spring Perches. EXB models using ARRMA #330740 Spring Perches may experience interference issues at both the shock mount and sway bars. RPM does not recommend the use of our a-arms on these vehicles since modification of the a-arms may be necessary to eliminate bind at the shocks and sway bars. Tech Notes: RPM Rear A-arms for the ARRMA Kraton 8S are sold as a pair. RPM A-arms replace stock ARRMA #ARA330590.