Its commonly known that most overdrives and fuzzes are copies of just a select few circuits such as the Tubescreamer for example. This is what the original Fulltone OCD was based upon however instead of using the traditional clipping diodes found in the TS-9 and 808 they used Mosfet's which have a much more "tube-like" reaction to dynamics and clipping.
The OD Glove for EHX is their take on this circuit and like many others, they have done a great job, compare for example the Joyo Ultimate Drive Also found on TonePedia. This circuit is very well-loved and does a great job of re-producing darker Marshall tones, if you're looking for a great pedal to use at home on your own then look no further as it'll take you all the way from overdrive into fuzz and distortion territory. However, beware of using these in a live environment as due to the darker low mid focus you can struggle to stand out in the mix without pushing the volume very high.