In the 70s,Maxon used the JRC4558 chipset and successfully created a much sought after overdrive pedal. Soon later, Ibanez, Boss and other pedal makers started to utilize this chipset and made JRC4558 so famous.With technology, we can use even better qulity JRC4558 chipsets to get a better sound! The biggest breakthrough of OD-8 in technology is ti allow users to change the chipsets to creat different tone that he or she desires without soldering or professional skills, just like changing a processor of a computer. Specifications: Model Number:OD-8 Connector:Input×1,Output×1,Power Connector×1 Power Requirements:S-006/6F22 9Volt Battery or DC 9V Regulated Power Supply Current:7mA Input Impedance:1MΩ Size:128mm(L)x94mm(W)x60mm(H) Package included: 1 x Guitar effect pedal