The Valcom VMT-1 transformer is designed to match inputs from or outputs to a 600-ohm line. Used as an input-matching transformer it connects telephone systems to most public address amplifiers for telephone paging. In addition it functions as an output-matching transformer to feed program material over a 600-ohm telephone line for music-on-hold. It is compatible with any amplifier having a 25V output connection. Hi-Z 10k-OHM Primary Impedance Lo-Z 600-OHM Secondary Impedance Balanced with Center Tap Matches High-to-Low Impedance or Low-to-High Impedance Adapts Line Level Signals to Microphone Inputs Phono Jack or Screw Terminals for Hi-Z Side Screw Terminals for Lo-Z Side Steel Enclosure with Mounting Ears Allows Easy Mounting Product Type: Impedance Matching Transformer Product Type: Impedance Matching Transformer Manufacturer Part Number: VMT-1 Limited Warranty: 1 Year Weight (Approximate): 8 oz Input Receptacles: Screw Terminal Output Receptacles: Screw Terminal Manufacturer: Windstream Intellectual Property Services LLC Product Model: VMT-1 Product Name: VMT-1 Impedance Matching Transformer Brand Name: alltel Brand Name: alltel Height: 1.8 Width: 3.8 Depth: 1.3 Input Receptacle Type: Screw Terminal Output Receptacle Type: Screw Terminal