The new SILENT Brass consists of a smaller, lighter, freer blowing Pickup Mute™, and the Personal Studio™, which features Yamaha’s exclusive Brass Resonance Modeling™. Used together, the two deliver the natural acoustic tone you hear when playing without a mute, making it feel as though you are playing mute free. Specifications Pickup Mute Model: PM5X Dimensions (Diameter x Length): 129 x 220mm (5-1/16 x 8-11/16) Weight: 155g (5.5 oz.) Internal Microphone: Electric condenser microphone Pickup Output Jack: Mini phone jack Nominal Level: -25dB~-35dB Brass Resonance Modelling: Yes Personal Studio Model: STX-2 Dimensions (W x D x H): 70 x 20 x 98mm Weight: 69g (2.4 oz) without batteries Jacks and Terminals: MUTE IN, AUX IN, PHONES Control: VOL. (volume), Reverb type, Power ON/OFF Brass Resonance Modelling: Yes (It behaves correctly only when compatible Pickup Mute is connected to Personal Studio.) Power Supply: AA alkaline or nickel-metal hydride batteries x 2 (3V DC) Included Accessories: Cable; Stereo Earphones; Owner’s Manual