Lugsulation flex has a molded sealing lip on both sides in form of an O-ring, which seals axially in the direction of the screw. On one side a cylindrical dome, which protrudes from a housing or similar, dips into the sealing sleeve and touches the internal contact element such as a tubular cable lug. The lower O-ring rests on the housing and seals there. The opposite side accommodates a screw, with a cylindrical step resting against the other side of the contact element. The head of the screw is plastic-insulated and has a mould on sealing surface which rests against the opposite second side of the sheathing and also seals axially against the second O-ring. Tightening the screw connection creates a surface pressure between the components. This creates an electrically conductive contact. As an example, this design can be used in European traction batteries according to DIN and British Standard. Suitable for sealing internal (female) and external (male) threads!