The Type Two superseded the 64 feet ( 20 m ) high speed launch .
Itself was replaced by the 68 feet ( 21 m ) Type Three HSL also built by the BPBC .
The Type Two superseded the 64 feet ( 20 m ) high speed launch , and itself was replaced by the 68 feet ( 21 m ) Type Three HSL also built by the BPBC .