The second oldest of the steamship company's boats is the "Wilhelm Tham", named after the industrialist and CEO of Husqvarna Weapons Factory from 1876-1911. Built at the Motala Werkstad as well, she was launched in 1912 and was one of three boats named to honor three of the area's living native sons. The other two were Victor Rydberg and Per Brahe. She became part of the steamship company in the fusion with Angbats Aktiebolaget Jonkping-Stockholm in 1914, was extended and given her current profile in 1961 at the Falkenberg Shipyard. One of the measures was to move her bridge forward under the mast, thus doubling the number of cabins. The steam engine was replaced by diesel in 1965.

The cabins are charming, but small! With the exception of the cabins on the main deck (cat. C) on board the M/S Diana (and some special cabins on the other two ships), the cabins are fitted with bunk beds and are about the size of a small sleeping compartment on a train. All cabins are above the waterline with a porthole (main deck) or a window. The cabins have a washbasin with hot and cold water. None of the cabins have private facilities. However, showers are provided on all decks (except shelter deck on M/S Diana), as well as toilets. The ships use 220 V electricity, with outlets in all cabins.