From the first clumsily mass produced tanks to post-war state of the art fighting machines, only one element remained present in Soviet tank design: the log.
The purpose of the log was simple: to help the tank climb out of mud where tracks don't have enough traction. Simply hook up the log to the front of your tracks, drive forward slowly with the log serving as an anchor in the mud, then unhook it from the rear and move it to the front of the tank, repeating the process until you're back on solid ground. However, simply any old twig you found lying around wasn't good enough. The log must conform to precise specifications.
The log must be 190-220 mm thick and 3280 mm long. A log that stretches out past the sides of the tank is explicitly prohibited. Clips to hold the log in place are also stored on the rear of the vehicle, whereas on older vehicles you would have to tie the log to the tracks with the tow cables.