This Staedtler Lumocolor Non-Permanent Universal Red Fine Line Pen is for use on overhead projector film and almost all surfaces including CDs and... Universal pen for use on almost all surfaces Suitable for overhead projection Can be wiped off film using a damp cloth Water-soluble ink Fast-drying PP barrel and cap guarantee long service life Airplane-safe - automatic pressure equalization prevents pen from leaking on board aircraft Stand-up STAEDTLER box Superb colour brilliancy Lightfast colour black Line width fine approx. 0.6 mm Refillable