This is On The Run 484 Refill Ink. This is the same ink used in the OTR 084 and 184 Flow Pen Markers. This ink is super permanent alcohol based ink. You can use it to refill your OTR Flow Pen or many other markers. The 484 Refill ink come in 200ml bottle. This is a great and cheap way to refill for Flow Pen or marker of your choice.