A laser includes a laser source and an power source arranged such that both components have substantially the same cross-section, with cooling fins arranged axially along the length of each element. The components are arranged end-to-end in a series to form an assembly with substantially the same cross-section along the entire length of the assembly. A shroud mounted along the assembly forms a single air channel directing air from a fan along the entire length of the assembly, for cooling both the power source and the laser source with the total air flow from the at least one fan. The laser source and the power source are arranged in series such that the laser source is cooled first, and the subsequent air flow, although slightly warmer from cooling the laser source, is sufficient to cool the power source.