Datadart Obsidian Darts - Steel Tip - 90% - Concave Rear - Black PVDDatadart Obsidian Darts Steel Tip 90% Concave Rear Black PVD. All Obsidian 90% Tungsten darts are individually packaged and include a set of durable stems and a set of Datadart flights. Datadart Obsidian Darts Steel Tip 90% Concave Rear Black PVD. All Obsidian 90% Tungsten darts are individually packaged and include a set of durable stems and a set of Datadart flights.