Specially developed ink is continuously driven to ballpen point by the internal pressure of a sealed refill; these characteristics enable writing and recording of data to be carried out in highly adverse conditions.
Write on damp/wet greasy paper. Write at any angle e.g. On noticeboards or even upside down. Write in extreme cold (-45°c) or extreme heat (+200°c).
Rubberized body of pen gives maximum grip in wet conditions.