The strait is about 150 km wide, as measured from Borneo to the island of Belitung. Belitung is separated from Bangka Island to the east by the Gaspar Strait. Bangka lies close to the east coast of Sumatra, separated by the Bangka Strait. The Karimata islands lie in the strait, northeast of Belitung and closer to Borneo.
A strait is a narrow channel of water that connects two larger bodies of water, and thus lies between two land masses.
Straits usually lie on important shipping routes, and many wars have been fought for control of these straits.
That is, while straits lie between two land masses and connects two larger bodies of water, isthmuses lie between two bodies of water and connects two larger land masses.
The KarimataStrait is the wide strait that connects the South China Sea to the Java Sea[?], between the islands of Sumatra and Borneo in Indonesia.
The strait is about 150 km wide, as measured to the island of Belitung[?], which is the end of a chain of islands starting with Pulau Bangka[?] off Sumatra's east shore.
There is also an eponymous small group of islands in the middle of the strait.