A dad who builds 3D-printed arms in his garage workshop has created a specially adapted bicycle for children missing an upper limb.
Adam Dengel, 30, created his first DIY limb in his bedroom for son Thomas, four, who was born without a hand.
He has since set up a charity and made superhero-themed prosthetics free of charge for children around the world.
For his latest project, he plans to surprise four children with their own custom-made bikes.
They cost £220 to make and are fitted with an ergonomic cup which allows the rider to reach the handlebars without leaning.
Mr Dengel said the modification makes the bikes safer to ride than a normal model.
The parts, like the arms, are created on Mr Dengel's 3D printer in the garage of his home in Royston, Barnsley, which he has converted into a workshop.
"These kids haven't had the best start in life and we wanted to help boost their confidence," he said.
"Plus this gets them outside, riding bikes with other youngsters, and helping them to make friends."
Mr Dengel, 30 and his wife Katie were inspired to help others through their experiences with their son.
Thomas was born with a short forearm and missing his hand due to amniotic band syndrome - a rare condition where stray bands of tissue wrap around the limbs of an unborn baby and cut off blood flow.
Unhappy with the basic NHS prosthetic, the couple started looking at alternatives and found a charity which made Thomas his first mechanical arm.
This led him to buy his own printer and set about creating a number of colourful, comic book-inspired hands for his son - including his latest Batman-themed prosthetic.
Through the couple's charity LimbBo Foundation, Mr Dengel has so far built 33 personalised arms for children, including youngsters in America and Holland.
"To say we the charity started out as an idea on the sofa we're thrilled with how things have gone," he said.
"We only ever wanted to help other kids like Thomas and it gives us so much pleasure to know we're doing that."