Ever wonder why PCB folks throw around "M8" or "M9" like a spec sheet magic word？

The "M" traces back to Panasonic's Megtron series - long the benchmark for low-loss， high-speed copper clad laminate （CCL）.

Each generation from Megtron 4 to 8 progressively lowered the dissipation factor （Df）， meaning less signal loss at high frequencies.

Because Megtron set the bar， it became industry shorthand for a performance tier rather than a Panasonic-exclusive part number. Say "M8 grade" today， and it simply means "meets Megtron 8 electrical specs" - whether it's made by Panasonic， EMC， or Doosan.

As AI servers demand ever-higher SerDes speeds， high-tier CCL has become the critical bottleneck material. That makes it one of the tightest， fastest-growing segments in the entire hardware supply chain.