Landsverk L-10
Landsverk L-10 (Swedish Army designation: stridsvagn m/31, abbr. strv m/31, "tank model-1931") was a Swedish late interwar era medium tank constructed by AB Landsverk for the Swedish Army between 1930 and 1933. The tank had an advanced design for its time, being the first tank produced to feature an all-welded construction and using periscopes for visibility rather than view slits. It was armed with a turret mounted Bofors 37 mm anti-tank gun L/45 (37 mm kanon m/34) and two Browning M1917 machine guns (6.5 mm kulspruta m/14-29), one coaxial mounted in the turret and one flexible mounted in the hull, and was equipped with  of armour. History 
Development of the L-10 started in 1930 as part of a competition set up by the Royal Swedish Army Materiel Administration (KAF) for the next generation of Swedish tanks. Landsverk competed against designs from AB Bofors (Krupp) and Morgårdshammar AB, evaluation being conducted in the fall the same year. Landsverks designs came out on top and Landsverk was selected as contractor in January 1931. After further in-depth evaluation of Landsverks designs, KAF ordered three L-10 test vehicles from Landsverk in October 1931, along one Landsverk L-30 trial vehicle (essentially an L-10 with deployable wheels). The three L-10 vehicles were built in 1933 and delivered to the Swedish Army in 1935. Armour was delivered by Bofors. Despite being highly advanced for their time, they often broke down when not handled properly, and lessons learned from their trials were incorporated into the much improved Landsverk L-60 (strv m/38). When World War II broke out, they were dug in as static bunkers due to a lack of spare parts, as many key parts were produced abroad. Landsverk L-30 (strv fm/31) 

The L-10 had a variant, known as the L-30, which featured deployable wheel propulsion in addition to its tracks, the idea being that wheeled and tracked propulsion could be quickly interchanged (in less than a minute, even while on the move) depending on the travel surface (road/terrain). A mild steel prototype with a wooden mockup turret was ordered in 1931 (designated stridsvagn fm/31: fm = försöksmodell, "trial model") along the three L-10 (strv m/31) and delivered to the Swedish Army for trials in 1935. Surviving vehicles 
One L-10 (strv m/31) has been preserved. The vehicles was exhibited at the Swedish Armour Museum in Axvall between 1969 and 2007, then on being moved to the collection of the new Swedish Tank Museum Arsenalen, were it have remained. Period Landsverk armoured vehicles 

Example list (incomplete)

Tracked vehicles
Landsverk L-5
Landsverk L-10
Landsverk L-30
Landsverk L-60
Landsverk L-62 Anti
Landsverk L-100
Landsverk L-101
Landsverk L-120
Landsverk Lago

Wheeled vehicles

Landsverk L-180
Landsverk L-181
Landsverk L-182
Landsverk L-185
Landsverk L-210
Landsverk Lynx

Railroad vehicles
Landsverk L-310
Landsverk L-320
Landsverk L-321

References

Further reading 
https://www.ointres.se/strv_fm31_m31.htm
http://www.wwiivehicles.com/sweden/tanks-light/strv-m31.asp

World War II tanks of Sweden
Tanks of the interwar period
Military vehicles introduced in the 1930s
20th century in Landskrona
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