Qu-Bit。ガイド付き電子ピアノ|ソースネクスト。Qu-Bit。Amazon.com: Keychron Q1 RGB Wired Custom Mechanical Keyboard Knob。EON is an envelope, oscillator, and noise source in 2 HP.https://www.qubitelectronix.com/legacyIt works perfectly well. I just have no space for it.Sold with screws & ribbon cable.Sorry I can't lower the price for now because JPY is very low...Neither returned nor exchanged.