Valve Art 845's

I have 4 x Valve Art 845's in my Momo Power Amps, they are marked 845 only, no B, C or M-does anyone know whether Valve Art mark thier tubes A,B M ?

Valve Art are rebranded Shuguang tubes. Valve Art marketed a aluminum based graphite plate (845A) and a copper based, graphite plate (845B)tube. I am almost positive that they did not market tjhe metal plate 845C or 845M tube.