Ordering piezography ink

hi, there there seem to be two different bottles of K7 HD matte ink, one says ultra HD on the bottle the other says HD … is there a difference cos it will only give me the one that says HD for my cart thanks. Also is it cheaper to buy the set or individual bottles as I don’t use the gloss and the optimizer carts … I have piezoflush in them. I have epson pro r 3800 printer. thanks chris

The UltraHD is the Matte Black (thus the name UltraHD MK) and the non-ultra (just HD) is Photo Black ink (HD PK).

Matte black is for matte papers. Photo Black is for Glossy papers.