Amdek DSK-100 Distortion
The Amdek series of pedals was produced by Boss in the 80's as a DIY approach to pedals. They were sold as kits and generally used original Boss circuits. The PCB's came assembled and the buyer simply soldered the hardware and screwed the pedal into place.
The DSK-100 has the feel of a 1980's MIJ DS-1 and has a similar tone and layout, however the actual circuitry is built around a NEC C4558C rather than the famous Toshiba IC that made the original DS-1's famous.