The original ergonomic pen and still the best! 

The RingPen is a result of prolonged research that started in an aerodynamic laboratory 20 years ago and incorporates ideas that are applied in aerodynamics and theory of stability. Approaches were similar to that used in the design of aerobatic airplanes. 

It is the first time in history that mathematical ideas were applied to the design of a writing instrument!  

The outcome is an ergonomic designed pen that is fluid in writing and fatigue free.