pla.
Got two free 500g rolls with my klic-n-print.
Worst filament I've ever tried. The white just snaps at random points either during, before a print or while just sitting on the back of the printer. Never had this with any other filament.
The black will print - but no matter what temp i tried - just can't get sharp prints wth it.
Even the dirt cheap ebay filament outperforms it with ease.
Maybe klic-n-print just gota duff batch. Who knows, but given how many seriously good, well priced brands of filament there are available in the uk - I've no need to ever buy esun :-)