Stabillo OHPen Universal Pen - 4 Color Set - 4mm Permanent

These pens are the optimal choice when it comes to overhead projection, however they also write on almost all smooth surfaces making them very versatile. They feature either permanent or non-permanent ink (black shaft indicates permanent ink, gray shaft indicates water-soluble) and are available in three tip sizes: superfine (.4mm), fine (.7mm) and medium (1mm).The body has a non-slip grip zone and the ventilated cap has a practical clip. The 4-color sets include black, blue, green and red.