Exactly --there are 2 M140s 1.8W China made and the Japan only made 2W The (older?) China made A-series M140 1.8W and newer Japan mase 2+W M140--is a DTR distinction based upon performance and originFrom what I know, there are A140's, M140 A types and M140 M types.
Seems to be lower output binned are called China mad M140 A-type and the 2+W M140 are called Japan M140thats true but the m140 A types are actually the same diode as A140. it just mean it harvested out of m140 projector which includes both of A and M types
At least that is how DTR has them sorted out.
Main difference between A and M is the number of contact filaments attached to the diode bar.
The A-series diodes have three contact filiments on each side spread evenly across the die from both posts
The stronger M series diodes have four contacts. The contacts on one side are spaced with three at the top of the die and one at the bottom of the die from one post.The four contacts, from the other post, are evenly spaced . Info and images courtesy of DTR's site