SemiNex Corp.’s four-pin fiber-coupled diode laser is available at 1450, 1470, 1532 and 1550 nm, or it can be manufactured for any specified wavelength between 1300 and 1600 nm. It delivers 4 W of continuous-wave optical power from a 105-/125-µm, 0.22-numerical-aperture fiber. It has a slope efficiency of 50% W/A and wall-plug efficiency of 30%. It includes a back-facet photodiode monitor. Laser light is emitted through a 650-nm aiming beam. The laser is maximized for aerospace, free-space optical communications, light detection and ranging, military and medical applications. The high slope efficiency lowers the standard electrical and cooling system requirements, allowing the design of smaller laser systems at reduced costs. The device offers high-heat-load capacities, enabling longer time in use, even under elevated heat sink temperatures.