These Staedtler Whiteboard Markers is ideal If you’re in a high-stakes meeting, high-school classroom, or running a university tutorial, if there’s a whiteboard up-front. The unique dry safe ink formula allows the cap to be left off for up to 48 hours without drying out. The alcohol-based pigment ink in the Staedtler has a non-offensive low odour and provides dense bold colours. The ink can be dry wiped from whiteboards and surfaces like glass and porcelain without leaving a trace. This lock tip, PP barrel and cap guarantee long service life as well Airplane-safe – automatic pressure equalization prevents pen from leaking on board aircraft. This refillable Black colour Whiteboard Markers can make Line width approx. 2.0 mm for smooth flow from the beginning to the end.