Short Wheel Base. This refers to the distance between the front and back wheels of a vehicle. Sometimes manufacturers offer a variety of lengths on a single model. This abbreviation is used to help differentiate between them.
Shallow water blackout. Caused by a dramatic reduction in the partial pressure of oxygen during an ascent, leading to hypoxia. As a result, the freediver experiences unconsciousness. There are no indicators to predict the onset of SWB.