Looks like you have to remove a washer between the purge cover and the plastic cover over the diaphragm before you try to unscrew the plastic cover. Proceed with caution here; you don't want to use some kind of tool that could rip the diaphragm. Tearing the diaphragm will probably kill the reg unless you find a source of parts for this thing.
I've never heard of this brand, but from the pics and schematic, this reg has a lot of Scubapro R190/380 in its lineage. Just be careful and you won't go wrong.
I've never heard of this brand, but from the pics and schematic, this reg has a lot of Scubapro R190/380 in its lineage. Just be careful and you won't go wrong.