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The Samix SCX10 II Short Aluminum Bumper Mount with adjustable servo mount serves two purposes. First, it moves the servo to the furthest forward point possible and maintains the correct geometry. Second, it allows you to push the bumper 4mm closer to the rails for increased approach angle.
Additionally, this mount is required when installing the Samix SCX10 II Samix Forward Adjustable Battery Tray Kit (SAMSCX2-6035). When both parts are combined, it allows you to mount your battery lower on the chassis, in a centralized position and keep the chassis mounted servo configuration.