uni-ball 1832404 VISION ELITE BLX Series Rollerball Pen .8 mm Assorted 5/ST Sold as 5/Set. Patented airplane-safe technology prevents leakage on flights. uni-flowTM system delivers a smooth and steady flow of water-resistant ink, ensuring skip-free writing with a consistent color. Exclusive pigment-based ink forms an indelible bond with paper for intense coloration and document security.