Features: Engineered with excellent anti meddling capabilities and high sensitivity (≥118dB/mW), the mining telephone microphone ensures clear communication in noisy environments through its 200Hz 4000Hz frequency response. This solid metal built communication device features 100mW top noise power control, moisture resistant construction, and seamless compatibility with magnetic/automatic telephone systems for responsible underground operations. Designed for miners, industrial technicians, and urgency responders working in electromagnetic heavy environments like coal mines, tunnels, and hazardous worksites requiring noise filtered voice transmission. Optimized for critical voice communication in challenging scenarios including underground mining operations, construction zones, and industrial facilities with persistent electromagnetic meddling. Its degradation resistant metal housing and broad device compatibility make this high sensitivity anti meddling microphone an essential component for maintaining operational safety and communication comprehensibility in extreme conditions. Specifications: [Substance]: Metal [Product Size]: 45.5x17mm [Product Weight]: 30g [Color]: Golden yellow [Frequency reach]: 200Hz~4000Hz [top noise power]: 100mW [Output Impedance]: 150-1000 [Average Sensitivity]: ≥118dB/mW (200Hz~4000Hz) Package Includes: 1 Piece Anti-meddling Mining Telephone Transmitter note: Please allow 1-2cm errors due to manual measurement. Please allow for slight color differences due to different display resolution.