The Lum-Tec Vortex D4 has the look of a classic military automatic but is driven by a solar-powered Japanese movement. Just one minute of sunlight gives it a full-day of power and with 5 hours sunlight for a full charge, it boasts a 6-month power reserve. The case is made of 316L stainless with a military-grade titanium carbide PVD hard coating. Available for pre-order now.