Mercury - 1st Mate Safety & Security System SmartCraft Dual-Engine Kit 98-8M6007934. Overview. Running a dual-engine setup adds power and capability, but it also raises the stakes when it comes to safety and security. The Mercury 98-8M6007934 1st Mate Dual-Engine Kit gives your boat an extra layer of protection-alerting the captain and crew if someone goes overboard and adding a meaningful theft-deterrent when the boat is unattended. With its intelligent hub, harness, captain's wearable, and RFI