The Psvane Shuguang 300B-Z/2, also known as the Matched Pair Black Treasure, is a premium grade A factory-matched pair that ships as such. This model features an improved structure for enhanced dependability and safer shipping. It includes gold-coated pins for long-term connection reliability. Notably, it utilizes High Polymer Compound Carbon (HPCC) coating, a first in vacuum tube production.

This coating allows for a higher concentration of electrons, enhancing and maintaining electron flow stability, maximizing suppression of secondary electron emission from the glass enclosure, and reducing internal noise caused by electron swirl. Only the highest grade parts are used, and assembly is carried out by highly experienced workers. A burn-in time of 80-150 hours is suggested.

The premium grade A quality is assured, with the lower budget grade B, or "regular" version, not available from Hot Rox UK.