All -R media manufactured by CMC, regardless of media code, starts with those type codes. The first three letters let you know the disc type (-R or +R), dye type and speed:
M= minus; P= plus
A= Azo; F= Fuji dye, T=?
D= 4x, H= 8x, P= 16x.
So a disc serial starting with PAH is an 8x +R disc using Azo dye.