Pair, each about 19x26" on heavy stock. Both are artist proofs w/pencil notation of "A/P" and each has been hand signed in pencil by Mouse who added his trademark small running mouse illustration to each. First is of the 1966 Matrix poster featuring Big Brother & The Holding Co. w/band image at the center. Lower right has "Running Mouse Serigraphy" stamped seal. Slight margin aging but Exc. Second is of the 1966 FD-31 Avalon Ballroom poster for Country Joe & The Fish featuring portrait image of Edgar Allan Poe. Bold image w/silver printing. Moisture staining at top left but not affecting art and could be easily matted out. Other margin wear but image area remains Exc. Both signatures are bold. Great pieces for framing. Comes with Hake's COA.