This is a Muff-style fuzz from Umbrella Company. The switches on the surface and the jumpers inside allow for a variety of sound creation, despite being a Muff-style fuzz. I liked using it, but I'm selling it because the sound I want to produce has changed. Velcro is attached to the back. All accessories are included (see image 6). Operation has been confirmed. Here's the manufacturer's description: Umbrella Company's "Mayonaise Fuzz" was born from a unique interpretation of the fuzz distortion sound that has been passed down to the present day. It is tuned to be classic and, at the same time, modern, respecting the character that everyone loves. While referencing many so-called masterpieces, it has a new sense of texture and operability. Rich and deep drive. Aggressive overtones that cut through. The biggest feature is the sound's projection, thoroughly conscious of being alternative. Furthermore, it is equipped with DOPING, which pushes the mid-range, and a 1979 switch that changes the gain structure. This allows for multifaceted sound creation suitable for the modern scene.