Atomik RC Traxxas Slash 4X4 1:10 Aluminum Alloy Steering Block Hop Up Upgrade, Blue Replaces Traxxas Part 6837 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 6837. Atomik RC Offers a Full Line of Hop Ups for your Traxxas Slash 4X4 1:10 Available in Red, Blue, Grey/Gunmetal.