Arm Bar/Elbow Immobilization is a skill common to just about every martial art expression that I know off. In Yu Shin Hapkido, attention is focused on proper timing of interception, push-pull principle, breaking balance, and penetrating versus spinning. This skill’s relationship to the sword and “upward extension (Dan Jun Ho Hup Bup)” is referenced. While this video clip is of marginal quality, I believe that it is worth viewing.