Documentary footage of 3 Lithuanian speleologists (Saulė Pankienė, Gintautas Švedas, Aidas Gudaitis) and 1 cave diver (Vytis Vilkas) diving through "Kvitochka" siphon and getting to siphon "Dva Kapitana" in Krubera Voronya cave, 2010 August.
Dive through siphon takes about 4 minutes, but it's cropped as it's not very informative due to poor visibility.