TOA ER-604W Portable Shoulder Megaphone, Powerful 10 Watt Amplifier, 525' Rated Distance, Detachable Handheld Microphone, Whistle Alert ToneKey Features- Compact and lightweight- Rugged construction- Proven TOA quality and reliability- Powerful 10 watt amplifier- 525' rated distance- Detachable handheld microphone with press-to-talk switch and adjustable volume control- Whistle alert tone — pushbutton-activated- Two microphone inputs — for optional headset and/or handheld microphones- Line input for CD player or other sound source- Battery powered (8x AA) — with low battery indicator- Standby mode — preserves battery life when using external microphone or line inputsSpecifications- Power source: 8x AA batteries (LR6), external power, 12 VDC/0.8 A- Rated output: 6W- Maximum output: 10W- Battery life: Voice, approx. 10 hours (R6P manganese dioxide battery use), whistle: approx. 30 minutes (continuous use)- Audible range: Voice/whistle: 525'- Microphone: Close-talking type, press-to-talk switch, volume control- Signal: Whistle, push switch activation- Input: MIC 1: -40 dBV, 1.5kΩ, 6.3mm phone jack; MIC 2: -18 dBV, 3k Ω, 3.5mm mini jack, w/phantom power, AUX: -12 dBV, 18 k Ω, 3.5mm mini jack, external power, 12 VDC- Operating temperature:-10°C to +40°C- Dimensions: 4.08" x 10.32" x 8.64"- Weight: 3.5 lbs- Accessory: 3.5mm mini plug: 1, external power supply cord: 1