He looked at contraptions that would pull him along underwater at speed – something like the AquaJet H2 or Scubalec, for example – but everything already available proved beyond his reach. So he decided to design and build the Cuda underwater jetpack, which will be going into production early next year.

O'Brien developed the Cuda while in his final year at the Loughborough Design School in Leicestershire, noting that existing products were either too heavy, too slow or far too expensive. His original idea was simply to try and shrink down a jet ski engine so that it could be worn as a jetpack, but this didn't hold water.