sorry for my english, i used google translate. 1)Russian soldiers wear boots, not shoes(like on this picture). only big problems with the production of leather, was forced USSR to temporarily return to the shoes in 1941-1942 years, then returned to his boots.
2) Shoulder strap. in the USSR was no epaulettes(Shoulder straps) 1917-1943 year. This was considered a legacy of the tsarist. In the period 1917-1943 buttonholes(петлица) were a sign of distinction in the army. (look here [link])