The PLEXperimental-50M is a home-built tube guitar amplifier that is based upon a model 1987 Marshall "plexi" amplifier.

The "MR Theremin" is a home-built all tube theremin based upon some early 20th century designs.

The MRR-250 is a similar petal to a DOD-250.

The RBG-2002 is a precision insectiod pest killer.