$60.99 Only decent 0.5mm pen I could find. Why is majority of pens 0.7mm? : pens
PIL31105 : Pilot® Pilot G2 Retractable Xfine Gel Ink Rollerball Pens - Extra Fine Pen Point - 0. 
JetPens.com - Ohto Petit-B Needle-Point Ballpoint Pen - 0.5 mm - Lavender Purple Body 
