It was a personal electric scooter customised for commuting, with a long battery life, storage space and fitted out with a seat and bag holder.
The boys were inspired to create The Magnum because they wanted an easy way to commute around the local area, particularly as traffic in the area had increased congestion.
Will Waters from Tauranga was also a finalist for a different invention.
The competition always showed a huge depth of innovation and creativity – with previous winners having gone on to jobs with the likes of Google, Microsoft and Instagram.
Skills Group chief executive Garry Fissenden said it was evident that what many of the student-built projects focused on solutions to issues that impact the environment.
These included a shower timer designed to save water to an automated weed killer for farming, a project addressing soil leaching and a device that measures levels of E. coli in waterways.
Winning students will receive a guided tour of Rocket Lab's rocket factory and Mission Control – as well as the chance to watch a "hotfire" test of its Rutherford rocket engines.
This year's prize will include business mentorship and an opportunity to tap into the GridAKL start-up community for advice on how to take their inventions to the next level.
Other sponsor prizes also included an internship with IT-based service provider, Datacom.
The winners will be announced at the Auckland awards ceremony at Datacom on November 7.