A pair of demo M-1s with black trim. The panels were rebuilt in 2009 and have the latest PX stator wire insulation and PX membrane. The backplates have toroidal audio transformers and solid state bias supplies. They are in very good cosmetic shape and in PERFECT operating condition. For those not familiar with Sound Lab full-range electrostats they are probably without equal in terms of clear, non-fatiguing sound with incredibly accurate timbre (tone color). I doubt you'll find a nicer pair of M-1s at this price. Wood trim can be changed at additional cost.