Vacuum tube preamplifier/booster designed for electric guitars. It adds thickness and brilliance like a tube amp while preserving the original sound quality. The 3-band EQ allows for a wide range of applications, from natural boosting to aggressive sound creation. The space-saving design makes it easy to incorporate into your effects board. True bypass specification. Specifications: ■ Guitar Preamplifier ■ Vacuum tube equipped ■ Features: ・Equipped with an Electro-Harmonix vacuum tube. ・Compact size without compromising design, with the vacuum tube on the exterior. ・Equipped with three types of tone units: Treble, Middle, and Bass. ・Uses carefully selected parts, such as audio-grade capacitors and metal film resistors. ・True bypass switching method. ・On/off indication with an LED lamp directly below the vacuum tube. ■ Power supply: Input voltage DC9 (2.1mm DC jack, center negative) ■ Current consumption: Approximately 180mA ■ Size: Approximately W64.0mm x D115.0mm x H77.5mm ■ Weight: Approximately 230g This is an unused, almost new unit kept indoors. This is an older model that has been discontinued. I also own the new 2s model, but... the older model has a much thicker sound, so I think this older model is more suitable for rock music. By the way, although not officially stated, there is a master volume when you open the back cover, allowing for fine adjustments. This is being sold to replace equipment.