This Staedtler Lumocolor Whiteboard Marker has a medium tip.These pens are dry safe which means they can be left for up to 8 hours uncapped.Lumocolor pens have excellent smudge proof and waterproof qualities on almost all surfaces due to the fact that the ink dries in seconds. This also makes them very useful for left handed users.This ink can be dry-wiped from whiteboards, year planners and surfaces such as glass and porcelain without leaving a trace.This is a pen that is not affected by changes in air pressure, thanks to \"Airplane-Safe Technology\'. In-flight leaks are caused by expanding air inside the ink chamber.