Automatic/ Manual Activation; Overboard Location Alert System Sends GPS Location With Clear Visual Signals And Bearing Data When Break In Its Virtual Tether To The Tag Within 8 Seconds Of Tag Going Missing; Wearable Tag With LED Indicator; For Use With Boats Up To 40 Feet; 3500 Hours Operational Life; Lithium Battery; 1.81 Inch Length x 1.38 Inch Width x 0.6 Inch Depth; IP67 Waterproof; FCC/ RED/ CE Certified; With Universal silicone Wrist Strap/ Stainless Steel Buckle/ Pre-Installed CR2477 Battery; Pack Of 4