Compact and Portable: It measured3.52.51.4 in, 5.2oz, it can faultlessly fit in your pocketMultifunctional: It has signal mirror,whistle,fishing hook and line. It can locate and map orientationSurvival essentials: The signal mirror and whistle are designed for survival using. The whistle is 100 dB. The signal mirror is 1.4 in in diameterUnique Design: It has a 0.43 cu in storage for fishing hook and line,and can store other small thingsMetal structure, waterproof and shockproof. It withstand temperatures of 50 degrees below zero. Ideal for camping, hiking, adventure, positioning, mapping, etc