This amplifier provides 22dB gain wherever you need it. DC power supply directly or via the coax cable. Metal housing included. Specifications gain: 22dB power supply: 12V to 15V / 3mA input- and output impedance: 50 - 75ohm frequency range: 10MHz to 150MHz dimensions: 86 x 36 x 24mm (3.4" x 1.4" x 0.9") - Hints : Put the amplifier as close as possible to the antenna.