From the article:
The T-26 was developed from the British Vickers 6-ton with the distinct purpose of directly supporting infantry formations. Originally designed in the late 1920s by the Vickers-Armstrongs company for the Royal Tank Corps, the design was promptly rejected leaving the designers with little choice other than to export the tank to countries that were less technically advanced in terms of tank design.
The Soviets acquired several Vickers 6-tons in the spring of 1930 for evaluation and testing purposed along with a licence to manufacture the vehicle. Surprisingly the design was accepted by the Red Army as the T-26 before development and testing had been fully completed.
The main armament consisted of two ball-mounted 7.62mm DT machine-guns mounted in twin turrets. To avoid potential disasters, the rotation of the turrets was limited to 265°. Armour protection consisted of up to 15mm, enough to protection the three-man crew from small arms fire and shell splinters but little else.