I'm new and this is my first post so go easy on me if it's rubbish!
5-10m of free filament or "INK" for use with 3d pens or printers. The page says "Approx 35g of filament, enough to print a small vase".
I've just got a pen on the way and the ink already arrived so is ideal to get started with hopefully.
Free delivery and no card details needed which is a bonus. FYI it looks like you can choose your own colour but you cannot, they send it at random (just noticed it does say this in the product title).
Update - looks like they removed the page that the link points to but if you go to the desktop site you should get a pop-up which lets you add the sample that way. (you can request the desktop site on most mobiles in your browser settings).