For that to work, the pen cap has to be airtight of course. That's suppose to keep the insides of the pen cap humid and prevent the ink in the nib from drying. There is a membrane that lets the water escape into the pen cap. Inside the pen cap, at the opposite end from the see through glass/plastic. Or if it's easier, you can unscrew the whole top. You can unscrew the top of the pen cap slightly to reveal two tiny holes that you can put under a running tap to refill the water reservoir. See the bubble in the photo above? It has capacity to hold a few drops of water. There is a water reservoir right at the top of the pen cap with a see through glass/plastic that allows you to see how much water is in it. The highlight of the pen is it includes a humidifier in the pen cap. This pen definitely does not compete with luxury fountain pens. The design looks very industrial that's for sure. The surface is matte black and has a nice texture that feels nice to hold. It's made of aeronautical grade 6061 aluminium throughout and has a nice hefty weight to it. The build quality of the pen is excellent. So I guess if the pen can use this ink, it should be able to use most India inks. This is not an ink you want to use in a fountain pen. It's an India ink that's not listed in the recommended list on the paper. I don't know the brand of the ink so for my review, I used Dr Ph Martin's Bombay Black instead. That's a cute 4ml ink bottle with India ink in it. There is also a list of recommended inks for the pen. The paper included has instructions on cleaning and dismantling the pen. The pen and the ink bottle were nicely cushion in foam. That's the cardboard packaging box that the pen came with. I received the two weeks ago and was able to test it before the launch of the Kickstarter campaign. At the time of this review, he also has a Kickstarter campaign running and hope to make the pen available to more people. Inigo Echeverria was frustrated that there aren't any modern fountain pens that could use India ink, so he designed one himself. It is designed by Inigo Echeverria, an urban sketcher and product designer from Spain. This fountain pen that I received is called IndiGraph. So when I was offered to test a fountain pen that claims to be designed for use with India Ink, I was like, 'What?!? Is that even possible?' That's the type of ink you don't want to use in a fountain pen. And you will notice the ink will stain the ink, becomes hard, and is difficult to remove unless you scrap it off with metal. This is the type of ink you would use with dip pens. Some India ink use a binding agent such as gelatin or shellac to make the ink permanent when dry. When it comes to fountain pens, the only thing you need to know is don't use India inks in them because they will likely clog the pen, and if you're unable to clean the ink out, make the pen unusable.

India ink fountain pen