B40
# 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
