General Information: The Finns used a surprising array of helmet types and Finnish helmets of the Second World War are almost a subcategory of collecting unto themselves. One of the helmets that they used was the Swedish Model 1937. The Swedes sent 20,000 of these to their Nordic neighbor. In 1940 the Finns purchased a manufacturing license for the M37 and produced a nearly identical domestic version that was called the Model 1940. The Wärtsilä company was the sole manufacturer of the M40. The company’s Kone ja Silta facility in Helsinki (R. Soininen, personal communication June 13, 2022) produced 66,893 of these helmets during the Second World War. The Friitala Nahka Oy company made the liners. The M40 was the only domestically produced Finnish helmet of the war. Post-war, a subsidiary of the Wärtsilä company converted a large number of M40 helmets into cooking pots (R. Soininen, personal communication, January 28, 2015).
On the smaller sized helmets six split pins hold the liner and chinstraps in place with one pair of split pins used to attach both the chinstrap and forward sections of the two rear liner pads. On larger sized helmets there are eight split pins with a separate pair of split pins used for the chinstrap attachments only. The Finnish M40 differ from the Swedish M37s in several ways. The M40s are painted greenish-grey whereas the Swedish M37s were gray, although ones used in Finland may be painted greenish-grey as well. Finnish helmets have a “W” along with a size embossed in the rim. The “W” stands for “Wärtsilä.” Many, but not all, of the Finnish helmets have a red decal in the dome that reads “Valmistanut, Wärtsilä=Yhtymä Oy.” There are some differences in chinstrap construction as well. (See photos below with M40 on left and M37 on the right.)
Displayed Example: This M40 is a classic example of the type with all its original components including the interesting Wärtsilä decal in the dome. It is marked “W75” on the rim and it has the extra set of rivets for chinstrap attachment that was a feature of the larger sizes.
Collector Notes: The combination of a relatively limited production run and the post-war conversions make the M40s one of the more difficult to find of the Axis country steel helmets. When they hit the market, however, they tend to be modestly priced.
* Lieutenant Björkstam, head of the IT company and TK correspondent Karunki inspects the IT man’s helmet that has been hit. Sankajoki September 23, 1941. “From the front.” Finnish Wartime Photograph Archive. The Finnish Defense Forces. Accessed June 11, 2022
 Marzetti. 2003. pp112
 Roudasmaa. 1997. pp73