Atomik RC Traxxas Summit 1:16 Aluminum Alloy Wheelie Bar Hop Up Upgrade, Grey/Gun Metal Replaces Traxxas Part 7184 Precision CNC Machined for Factory Spec Fitment. Hardened Billet 6061 Aluminum for Lightweight and Durable Performance. Easy Upgrade from the Original Part. Replaces Traxxas Part 7184. Atomik RC Offers a Full Line of Hop Ups for your Traxxas Summit 1:16 Available in Red, Blue, Grey/Gunmetal.