Pen refill made with stainless steel with an enhanced tungsten roller ball (with golf ball type dimples to deliver the ink uniformly to the paper). The refill is of magnum design to allow writing for 26,000 feet. The ink is certified archival in accordance with ISO 11798 which prevents fading by time. Offered in blue or black color and with "fine" or "medium" tip. Delivered in 12-pack for each type offered.