Pilot FriXion pens come in 12 different colours and can be purchased in packs of 12, 6 or individually. They work, as you might have guessed, by friction- a novel idea for colouring pens. Each pen has a hard plastic nub on the lid that is used to 'rub out' the colour, leaving your normal eraser redundant and therefore eliminating rubber debris. The ink doesn't actually rub off the page though, it cleverly turns transparent when friction is applied (and if you leave the page in the freezer for a while the colour will reappear!).
These are going to be pens I use very regularly when I'm working on a project I want to be just flawless, and I have to admit the function of rubbing them out works so well it's great just to have a play!
Pilot Frixion Colours are available to buy at Cult Pens with FREE UK delivery :) A pack of 12 is £18.99, 6 is £9.99 and individual pens are £1.79.