Danger, Will Robinson...!
The Epson Stylus Pro 3880 has been replaced in the Epson lineup with the Epson Surecolor SC - P800. it is an even more capable A2 -sized printer and will become the standard of the line - just as the Epson Surecolor SC-P600 will take over the position formerly occupied by the Stylus Pro R3000.
Epson have packaged the new inks for the Sc-P600 in boxes quite different in appearance from that 157-series inks that serve the R3000. No-one will ever mix up the boxes and you won't choose the wrong ink.
Not the case with the new inks for the P-800. Their boxes are nearly identical with the ones for the 3800 and 3880. see the heading page - the T5802 is for the older models and the T8502 is for the new SC- P800. If you don't look carefully, you might pick up the wrong ink - and Epson CONFIRMED that the new inks don't fit the 3800 or 3880.
We'll be racking them separately in the printing section but please check the label carefully with any of these inks.