While most divers remember that their regulators need servicing and that cylinders have to be tested, not everyone realises that BCs and Wings need checking as well.  What is it that we do?  The more obvious checks are making sure that they will actually stay inflated!  However, BCs have compartments that we have to check are not damaged, hoses to inspect, valves and connectors to clean and service and Velcro and buckles that must be cleaned and checked.  When you need it for surface buoyancy, you need to know it will do the job!