Sea-Dog Battery Tray w/Clamp f/27 Series Batteries [415057-1] Brand_Uniden you can easily obtain quick

you can easily obtain quick magnetic bearings on shore or floating objects

Attached whistle for safety

Protects the battery against excessive discharge and can be used as a system on/off switch The Smart BatteryProtect disconnects the battery from non-essential loads before it is completely discharged (which would damage the battery) or before it has insufficient power left to crank the engine

but also gives you the battery status by pressing a button

but none offer three device connection

Sea-Dog Battery Tray w/Clamp f/27 Series Batteries [415057-1] Brand_Uniden you can easily obtain quickBattery Tray with Clamp for 27 Series Batteries Heavy duty Battery Tray for size #27 batteries. Includes screw down clamp and four 1 4"x1" PH screws with washers. Injection molded polypropylene construction. WARNING: This product can expose you to chemicals which are known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings. ca. gov.