A connection ring is provided for removable attachment of a fuel supply unit on a fuel tank. The connection ring has a ring upper side, at least one attachment elevation which protrudes from the ring upper side, and at least one tool engagement region. The tool engagement region is constructed such that a torque from a tool can be transmitted onto the connection ring. At least one portion of the tool engagement region and one portion of the attachment elevation are at an equal distance from the center of the connection ring in the radial direction from the center.