I’m not familiar with Hao pedals, so when I saw this mentioned on Twitter, I wanted to take a closer look. Apparently they’re hand built in Japan, and are quite popular over there. Hao also makes a Rust Driver that is coined as a ‘plexi in a box’.This is the Hao Rust Booster III. I was able to find a video on the Hao Rust Booster (non-III). It looks like they changed the boost to drive on the label. I’m sure there is some circuit modifications between the two.
Here is the official description of the Hao Rust Booster III Shred Booster Pedal:
The Hao Rust Booster III Pedal gives you an instant signal boost with no tonal coloration. The Rust Booster III Shred Booster Pedal is simple, yet versatile with both Boost and Level knobs. When the Boost knob is cranked, the Rust Booster stompbox produces crunch overdrive without sacrificing your guitar’s original tone. Clean or dirty, the Rust Booster effect will surely be a “must-have” on your pedal board. Bass players will also love the Rust Booster for its ability to boost bass signals without sounding thin and muddy.
Here is a video posted by grindingmass: