The metal encased spring loaded nib prevents bending and breaking. The micro cushioning creates a relaxed feeling whilst writing or mind mapping. Excellent writing comfort even under pressure at school or university. STABILO SENSOR is ideal for use with a ruler due to its fine tip. The line width of 0.3mm is perfect for mind mapping or colouring. Metal encased fineliner nib with a spring so tip does not bend, break or disappear; Relaxed feeling whilst writing; Excellent writing comfort, even under pressure!; Well suited for use with a ruler; Line width 0.3mm;