UNI-BALL POWER TANK SN-220 1.0MM NIB RED INK Uni-Ball Power Tank SN-220 1.0mm nib Red ink The Power Tank RT can write clearly upside down, in minus temperatures and on wet paper without blurring The ideal pen for those who work outside or enjoy outdoor leisure pursuits Additional features are a comfortable grip that cushions fingers, a convenient retractable function for easy use in more challenging conditions and a useful ink supply monitor. RED INK