title: B40
text: # B40
  
  B40, B-40, or B.40 may refer to:
  
  ## Roads
  
  * Autovia B-40, a Spanish motorway in Catalonia
  * Bundesstraße 40, a German road
  
  ## In Science
  
  * Borospherene, $B_{40},$ an allotropic cage-like molecule of pure boron
  * HLA-B40, an HLA-B serotype
  
  ## Military
  
  * Vietnamese designation of the RPG-2, the first rocket-propelled grenade launcher designed in the Soviet Union
  * BSA B40, a 350cc British motorcycle
  * Blackburn B.40, an experimental Blackburn flying boat
  * Rolls-Royce B40 Engine, an inline-four petrol engine primarily used in the Austin Champ
  * Unterseeboot B-40, World War I Imperial Germany Navy submarine U-boat
  * YB-40 Flying Fortress, an aircraft
  
  ## Other
  
  * 40 amp, type B – a standard circuit breaker current rating
  * Sicilian Defence, Encyclopaedia of Chess Openings code
  