Feature●Attention-getting telephone alerts designed for use in noisy locations and/or for medium●Typical applications would be factories, repair shops, printing shops, loading platforms, and warehouses●Uses a durable, high torque, permanent magnet motor-driven mechanism and 6" low frequency aluminum bell shell to produce a higher sound output and lower resonant frequency than conventional mechanical bells●Includes an extremely adjustable, tamper-resistant volume control, and are designed for both indoor and outdoor applications●Perfect for both Indoor or Outdoor applicationsDescription Wheelock Loud BellWHTB-593 Telbell is a loud attention-getting telephone extension alert designed for use in noisy locations and/or for medium to large area coverage. For single-line applications only. 95 DB- Dimensions: 6" in diameter line powered.