The continued increase in available power from femtosecond laser sources has enabled a wide range of micro-processing applications, including medical device fabrication, electronics manufacturing, and precision glass machining. Today, the emergence of commercial affordable >80W femtosecond lasers offers new opportunities in advanced manufacturing and research, but also raises key challenges. Especially developing robust fiber delivery for the industry is strategic to open new applications, ease the use of femtosecond lasers in huge factories, operate on e robot arm enabling larger and more complex  parts processing, or stabilize even further the laser beam.

This paper shows how the combination of mode-cleaning - a passive beam stabilization method based on Multi-Plane Light Conversion (MPLC) - with a fiber delivery system provides a promising solution for stable and efficient beam transport in high-power femtosecond laser applications. The mode-cleaning capabilities to at the same time correct any beam imperfections (ellipticity, asigmatism, M2…), and provide a stable beam despite input beam fluctuations (tilt and shift) will be demonstrated. We will discuss how power transmission remains high and fluctuations are significantly reduced during operation, even over extended operation times. Altogether, these results support the reliable deployment of next-generation ultrafast laser systems in industrial and scientific environments where beam quality and robustness are critical.