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25 August 2015 Last updated at 11:43 BST
Open Bionics says its device can be made faster and more cheaply than current alternatives.
It intends to launch a service next year that will 3D-scan amputees and then build and fit them with a custom-fitted socket and hand for about Â£2,000.
Olly McBride showed the BBC's North America technology reporter Dave Lee how its current prototype works.
A prototype 3D-printed robotic hand is this year's UK winner of the James Dyson Award.