LAMY M16 are giant ballpoint pen refills. The ink is waterproof.

Available in 2 tip sizes:
Fine – 0.08 mm
Medium – 0.10 mm

Both tip sizes come in black and blue colours.

The M16 pen refill fits the following LAMY Ballpoint Pens:
LAMY Imporium            LAMY Safari
LAMY 2000                    LAMY Lx
LAMY cp 1                     LAMY Logo an Logo M+
LAMY econ                    LAMY Pur
LAMY Noto                    LAMY Xevo
LAMY Al-Star                 LAMY Scala
LAMY Ideos Pd              LAMY Accent
LAMY Studio                  LAMY Aion