VEAK 40 (stands for Vagn, Eldledning, AutomatKanon, "40" being the caliber) was designed to provide the Royal Swedish Army with a tracked short-range anti-aircraft weapon system. At that time, Sweden only relied on towed Bofors guns and a few outdated Lvkv fm/43 SPAAG of WW2 design.
The project started in 1960 but the first prototype was delivered first in 1964. It used the Strv 103's chassis, mounting a twin 40mm autocannon. It was intended to be equipped with a newly developed Ericsson radar, but the latter was finally replaced by an existing older radar instead, which was underpowered and had limited scanning capability. The intention was to work around this with bigger radar stations feeding the crew information about which direction and altitude to scan at. Engagement range was to be pretty short.
Despite that, the VEAK was of an advanced design and showed promise, but the project was nonetheless ended because it had already exceeded projected costs, and the Army had then decided to focus on the air force.
Major Selekhov, Soviet intelligence officer, has some hard time analysing recon pictures brought back from an MiG-21R mission over Sweden. One picture inparticular gives him and his men some troubles
Selekhov finally order another low-altitude recon mission in this area, hoping to get a better view at that strange unit. Although the view is much better, he still can't match the vehicle with anything in his NATO armory book.
Finally, a Soviet spy infiltrated in Sweden is able to transmit a more detailed pictures, proving some theories right...