The four Year 13 students came up with the idea after one of their fathers, a farmer, complained about post hole drilling.
"He found it really taxing and said we should come up with a device so the four of us put our heads together and came up with the concept. We went through three prototypes before we got to this one."
The invention won the Fieldays Young Innovator of the Year award at an innovation awards breakfast at the national agricultural expo today.
The boys, aged 17 and 18, had already had success in the "crocodile pit" at St Paul's where they presented the invention earlier this year.
They hope to enter the crankholder in another national award later in the year run by Young Enterprise.
Mr Gordon said the next step was to patent the crankholder and begin selling the product.
He said feedback to the exhibit at Fieldays had been overwhelmingly positive.
"We've had quite a bit of interest. A lot of people are giving us tips on how to develop it further. A lot of people have been saying it's a neat idea and saying there's a massive gap in the market and they wish they'd come up with this idea 30 years ago."
The teens will present the crankholder to fencers at Fieldays competing in the Golden Pliers competition tomorrow for further feedback.
In total 70 entries were made to the Fieldays Innovations Awards with the trend toward mobile apps and data collection software as the industry keeps up with technological advancements.
Fieldays chief executive Peter Nation said the level of ingenuity was second to none.
"It's great to see the number of Innovations entrants growing every year. You're looking at innovations today that could very well revolutionise agribusiness tomorrow."
He said the inventors were tuned into innovation in a big way.
"We don't grow, we don't advance without stopping and asking the pertinent questions about where we are, how we got here and what it will take to move forward.
"Looking around the Innovations Centre today, the right questions are being addressed."
Other winners in the Fieldays Innovation Awards were:
• Vodafone Innovation and Technology - Agricultural Software Limited, FarmWalker Pasture Meter
• Locus Research Innovation Award - Kevin Bain, Pest Trap Reset Mechanism
• Origin Innovation IP Award - Progressive Equipment Limited, Pipe Grabber
• Crowe Horwath Agri Innovation Award - Styx Solutions, Styx Batten and Outrigger System
• Tompkins Wake IP and Commercialisation Award - Antahi Innovations Limited, TrutiTuber and FlexiTuber
• Tru-Test Prototype Grassroots Award - Kevin Bain, Pest Trap Reset Mechanism
• Tru-Test Prototype Established Award - Styx Solutions, Styx Batten and Outrigger System
• Fieldays Launch NZ Award - The Wrangler Limited, Pollen Smart