Abstract: A tube passage sealing system for allowing passage of a tube from the interior to the exterior of a case such that the case is sealed against fluid intrusion whether a tube is present or absent. The tube passage sealing system generally includes a case having a first portion and a hingedly connected second portion. The portions may be closed together to define a compartment in which a device may be positioned. A tube seal assembly is included which allows a tube leading from the device within the compartment to exit the case through a passage formed in the assembly. The tube seal assembly generally includes a first tube seal and second tube seal which combine when the case is closed to seal around the tube. Some embodiments may include blocking portions on the tube seals which will act to seal the passage when a tube is not present.