Here we have a pre owned Weber MASS 50 watt power attenuator for electric guitar amplifiers. Red and black chassis. Designed for use with amplifiers at 35 watts and below.  The Weber Mass is a perfect way to tame that loud tube amplifier.  When you need to crank your amp to get "that" sound.  This device goes in between your amplifiers speaker output and the speaker. Can be used with a head or combo amplifier.  This Mass 50 has  two speaker outputs, line out, and headphone out. Its amazing for recording or live use.  The tone stack on the front is for use with the line output for further tone shaping.   This unit is in great shape with a few scuffs on the exterior.  No speaker cables are included.   Thanks for looking and happy buying!