A laser assembly for generating an output beam includes a first module assembly, a second module assembly, and a module fastener assembly. The second module assembly is selectively movable relative to the first module assembly to selectively adjust a cavity length, and a pivot axis of a grating in the laser. Further, an arm assembly that retains the grating can be adjusted to adjust the cavity length, and to adjust the plane of the grating face. Moreover, the grating is movable relative to the arm assembly to align the grating.