The Fiber Laser Oscillator Core Module (FMSPW) is a Micro-optic package containing the core components for a mode-locked fiber laser. The package is available for different wavelengths, e.g. 1560nm, 1030nm and 1064nm, and includes a saturable absorber mirror (SAM) for mode locking as well as a lens pair for the optimization of the SAM performance. Optional it can be delivered with a fiber based pump port with a dichroitic mirror, polarizer or active polarization maintaining fiber.