Rotary transmission leadthrough provided with a gas return line

A rotary transmission leadthrough with a gas return line, the rotary transmission leadthrough being configured for filling a vehicle gas fuel tank, the rotary transmission leadthrough comprising:

• a supply line and a return line arranged in a coaxial manner in relation to each other, the supply line comprising a first connection adapter, the return line comprising a second connection adapter, the first and second connection adapters being arranged coaxially in relation to each other;
• a rapid-action connection coupling connected to the supply line and the return line, the rapid-action connection coupling comprising a housing;
• a rotary sleeve having an annular collar, a first union nut enclosing an outwardly sealed annular cavity, a second union nut clamping a counter-sleeve to the annular collar, a ring provided around the second union nut, and a plurality of axially-extending slits between the ring and the second union nut,
• wherein the rotary sleeve is rotatably connected with the housing and opens into the annular cavity, wherein the first and second connection adapters are arranged within the first union nut, and wherein the ring is rotatably held on the second union nut.