Designed to write in extreme conditions, the uni-ball Power Tank RT Retractable Ballpoint Pen features a pressurized tank so you can write upside down. It even works in extreme conditions, including on wet surfaces or in cold temperatures. The retractable pens also come with a durable pocket clip and a textured grip for greater comfort. Pen Sub-Brand & SKU Line: Power Tank RT; Pen Style: Retractable; Pen Type: Ballpoint Pen; Refillable (Yes/No): Yes.