Schatten Design MicroPre-2M Platine Preamp Two Channels, Specifications: two channel Jfet preamp, input - two separate channels in, condenser mic on channel one, pickup on channel two, output - two separate channels out, can be ganged for mono output, input impedance - up to 10 MOhm, output impedance - less than 3.5 KOhm, battery life - 9 volt alkaline: 1000 hours or 2 CR2032 coin cells providing a total of 6 volts: 375 hours (batteries are not included !), size: 1 1/4" long x 1" wide x 3/16" thick (28.5mm x 25.4mm x 4.5mm).