MITSUI SENPAKU K.K.

An earlier plain funnel was soon changed. M101 initially survived the change of company name, and black-and-white photographs in Jordan confirm its form, although some sources leave a wider gap between the bands.

The M100 funnel was adopted in the 1950s, with Watt showing no black top. Merchant Ships 1959 calls it greenish-grey; the 1959 and 1963 editions illustrate M101 while describing M100 without a black top.

The three bars represent Mi or Mitsu, meaning three. Kirsch explains the enclosing square as a stylised kanji for a well, read i, giving Mitsui the sense of three wells. FOTW replaced Phil Nelson’s Stewart-based flag with Bakker’s National Maritime Museum version. The museum flag, dated 1955–67, has central bars thicker than the surrounding frame; the source labels it M110 in the narrative but M100 in the source list.