R39 may refer to:
*
R39 (New York City Subway car)
*
R39 (South Africa), a road
* , a destroyer of the Royal Navy
*
R39: Danger of very serious irreversible effects, a risk phrase
*
R-39 Rif
The R-39 Rif (NATO reporting name: SS-N-20 ''Sturgeon''; bilateral arms control designation: RSM-52) was a submarine-launched ballistic missile (SLBM) that served with the Soviet Navy from its introduction in 1983 until 1991, after which it ser ...
, a Soviet submarine-launched ballistic missile
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