He was inspired to come up with the design after breaking his hand and was fitted with a conventional cast that was itchy, difficult to scratch and impossible to wear under long sleeved shirts.
"Wrapping an arm in two kilos of clunky, soon to be smelly and itchy, plaster in this day, seemed archaic to me," he said.
His solution was to scan his fractured hand with a 3D printer to produce a reconstructed 3D model. Parts of the cast are then snapped together to create a snug fit on the broken limb, and ventilation comes to the arm through its 'holey' membrane.
Auckland designer and finalist Nick Marks created the Tahr Quad, which remains stable on rough farm terrain.
Four wheel quad bikes that have tipped or rolled are responsible for 850 injuries in New Zealand every year.
The Tahr Quad was a bike designed specifically for farming, which uses a different suspension and chassis system in combination with intelligent computer technology to prevent it from rolling.
The third finalist, Evan Thomas from Wellington, created a chair that can be custom designed by the consumer.
The Fabseat is a desk chair that people can create for themselves by using materials that have been cut to their individual body measurements and cushioning preferences. The chair is designed online by the individual, materials are then sent from local suppliers, and it is up to the person to follow simple steps to build their unique slat chair.
"Fabseat is not a standardised chair. It's a scratch-built piece of furniture custom-made by the owner," Mr Thomas said.
The national winner will travel to the UK for the London Design Festival next month. They will earn a $3000 cash prize for travel, plus an official fee package from the Intellectual Property Office of NZ.
The winning New Zealand entry will be unveiled at a ceremony to be held in Auckland next Thursday.