The U16 was commissioned on and a type 7C Uboat This type UBoat was equipped with a new type of toilet designed to allow the submarine to dive deeper and avoid Allied attack It was a very complicated high pressure valve system which required special training to use themIn 06, a group of divers from Ardmore Diving discovered the wreck site of U1276 some nautical miles (37 km;First dive on the German UBoat U12Buchan Shipwreckswwwbuchandiverscom
German Submarine U 604 Wikipedia