Sealing cuff for sealing at least two light trunking elements, such as light trunking support rails and end caps, of a light trunking system, which light trunking elements adjoin one another on the end faces in a joint region and each extend away from the joint region along a relevant longitudinal axis, the sealing cuff having: • a seal support and • a sealing element, the seal support having a support part for each light trunking element for receiving respective longitudinal end faces of the light trunking elements, the longitudinal end faces facing the joint region, and each support part at least partially encircling a receiving space extending around a support part longitudinal axis for receiving the relevant longitudinal end face, characterized in that the sealing element has a sealing web which protrudes from the seal support in an extension direction such that the sealing web separates the receiving spaces and, in the installation position, projects into the joint region for sealing contact with the light trunking elements on the end faces, and at least two cross sealing webs (31, 32) extend from the sealing web for each receiving space, which cross sealing webs are arranged offset from one another in the extension direction and project transversely to the extension direction towards the receiving space for sealing contact with the light trunking elements. • a seal support and • a sealing element, the seal support having a support part for each light trunking element for receiving respective longitudinal end faces of the light trunking elements, the longitudinal end faces facing the joint region, and each support part at least partially encircling a receiving space extending around a support part longitudinal axis for receiving the relevant longitudinal end face, characterized in that the sealing element has a sealing web which protrudes from the seal support in an extension direction such that the sealing web separates the receiving spaces and, in the installation position, projects into the joint region for sealing contact with the light trunking elements on the end faces, and at least two cross sealing webs (31, 32) extend from the sealing web for each receiving space, which cross sealing webs are arranged offset from one another in the extension direction and project transversely to the extension direction towards the receiving space for sealing contact with the light trunking elements. the seal support having a support part for each light trunking element for receiving respective longitudinal end faces of the light trunking elements, the longitudinal end faces facing the joint region, and each support part at least partially encircling a receiving space extending around a support part longitudinal axis for receiving the relevant longitudinal end face, characterized in that the sealing element has a sealing web which protrudes from the seal support in an extension direction such that the sealing web separates the receiving spaces and, in the installation position, projects into the joint region for sealing contact with the light trunking elements on the end faces, and at least two cross sealing webs (31, 32) extend from the sealing web for each receiving space, which cross sealing webs are arranged offset from one another in the extension direction and project transversely to the extension direction towards the receiving space for sealing contact with the light trunking elements.