An adapter for connecting a hollow-body object to a device for washing through the inside of hollow-body objects, wherein the adapter comprises an inner part and an outer part at least sectionally surrounding the inner part, wherein the inner part and the outer part are movable relative to each other and extend along a longitudinally extending axis, wherein the outer part comprises an outer part wall with at least one latching device, characterized in that the latching device comprises a break-through in the outer part wall, a body movably mounted in the break-through and a movement limiting device (17, 24), wherein the break-through comprises a first opening in an inside of the outer part wall oriented towards the inner part and a second opening in an outside of the outer part wall, wherein a radial direction extends from the first opening to the second opening, wherein the movement limiting device (17, 24) limits a movement of the body extending in the radial direction to the second opening and prevents that the body can completely pass through the second opening to the outside, wherein the first opening has a diameter which is greater than a cross-sectional diameter of the body, wherein the latching device can be adjusted between a release position and a latching position by a movement effected by means of a relative movement between the outer part and the inner part, wherein in the latching position the body is arranged in the breakthrough radially further to the outside than in the release position, wherein in the release position an outside of the latching device does not protrude beyond an outer circumference of the outer part wall, but in the latching position extends beyond the outer envelope of the outer part wall. wherein the adapter comprises an inner part and an outer part at least sectionally surrounding the inner part, wherein the inner part and the outer part are movable relative to each other and extend along a longitudinally extending axis, wherein the outer part comprises an outer part wall with at least one latching device, that the latching device comprises a break-through in the outer part wall, a body movably mounted in the break-through and a movement limiting device (17, 24), wherein the break-through comprises a first opening in an inside of the outer part wall oriented towards the inner part and a second opening in an outside of the outer part wall, wherein a radial direction extends from the first opening to the second opening, wherein the movement limiting device (17, 24) limits a movement of the body extending in the radial direction to the second opening and prevents that the body can completely pass through the second opening to the outside, wherein the first opening has a diameter which is greater than a cross-sectional diameter of the body, wherein the latching device can be adjusted between a release position and a latching position by a movement effected by means of a relative movement between the outer part and the inner part, wherein in the latching position the body is arranged in the breakthrough radially further to the outside than in the release position, wherein in the release position an outside of the latching device does not protrude beyond an outer circumference of the outer part wall, but in the latching position extends beyond the outer envelope of the outer part wall.