Mercury - Gen I Throttle and Shift Cable 23 Foot Mechanical Engine Control 8M0085958. The Mercury Gen I Throttle and Shift Cable is built for boats using Mercury mechanical control systems that require a direct, dependable connection between the control box and the engine. Designed for legacy Gen I control interfaces, it delivers a familiar, hands-on feel at the helm with predictable throttle response and clean gear engagement. The 23-foot (7.0 meter) length is well suited for longer console-to-