This is so cool, the meter alone is worth the price. This is a Webster Electric WSC515 with WSC 516 tube microphone pre amp. This is the Webster version of the Altec 438 compressor but features some basic improvements on the Altec. It has nice heavy input and output transformers that look to be made by UTC and Triad. One of the improvement is the fact that you can balance the tubes like on the EMI RS 124 which is really essential on these to keep them from thumping during compression. They feature a tube transformer balanced microphone pre amp that also has a quarter inch input so it can be also be used for direct input like guitar or keyboard, the pre amp uses a 12AU7 and a EF 86. You can also bypass the compressor so it can be used as a straight pre amp or pop the compressor in and you have a compressor on the back end of the pre amp. The compressor controls are just input and output as I remember like a LA2 the more input the more compression. These are great sounding units I think way better and more useful than their Altec counterparts. This one has been recapped and comes a partial set of NOS tubes.