SWB stands for “short wheel base” recumbents. These are the numerous models that have the front wheel conveniently tucked under the pilot’s knees. There are a load of versions but the basic shape remains the same, little wheel in front, big wheel in back. High racers, mid racers, and low racers are swb bikes with some argument over the low racers. There are as many manufacturers out there as there are home builders so the selection is limited only to your particular desires and of course wallet.  This is my current SWB, an Action Bent Tango.  At least it was supposed to be a Tango.  Their site lists the Tango as a chrom moly bike and the Tango GT as an aluminum model with front disc brakes.  I got the aluminum frame but no front disc capability (so goes AB).  I should reference that “box of chocolates” thing here but will not.  I really like this ride but it does pass every bump and ripple right into my backside.  This bike is an “above seat steering” bike.  SWBs also come in “under seat steering” models.  The most common reference is “OSS” for over seat and “USS” for underseat.  I think somebody looked at the abbreviations and decided it was a bit more proper to call the above seat steering bikes, over seat steering bikes then have to explain why they ride an ASS bike.  The second SWB was my first two wheeled recumbent an AB Jetstream.  She came from New Orleans and I had a blast with her but alas she had to go to make room for other toys.