Uni-Ball® Jetstream 1.0 MM Blue Medium 101 Rollerball Pen Offer Excellent Writing Quality With Quick-Drying Ink That Prevents Smudging. The Ink Is Specially Formulated In A Way That Helps Trap It In Paper, Preventing Document Altering And Check Washing. Ink Is Formulated To Become Trapped In Paper, Which Helps Prevent Check Washing And Other Document Altering.