He has short ones for sitting and climbing and long fancy ones for when he wants to run really, really fast.
Cody McCasland was born without a working set of legs - but now has pairs for just about any occasion.
The seven-year-old has a rare condition called Sacral Agenesis which caused deformities to his spine in the womb.
He arrived without any tibia or knee bones and had to have his legs amputated below the knee at 15 months.
Growing boy: Cody shows off his different sizes of prosthetic legs - he outgrows them as fast as he gets them
Two months later he was fitted with his first pair of prosthetic legs, and hasn't stopped moving since.
His mother Tina, 36, said: 'Hardly anyone takes to prosthetics so well. It was amazing - it was as if Cody had just been waiting for the chance to have new legs so he could walk.'
Cody now manages to run, swim, play soccer, golf, karate and ice hockey as well as being a boy scout and going rock climbing in his home state of Texas, in the U.S.
Mrs McCasland said: 'We've always said whatever Cody wants to do, we will do our best to let him have that opportunity. He won't let his disability hold him back.'
Cody McCasland is already racing against able-bodied children, and hopes to compete in the Paralympics when he is older
As a result of his condition, Cody also needed surgery for a dislocated hip, stomach, gall bladder and intestinal problems and a hernia, as well as treatment for breathing difficulties and asthma.
His legs are provided for him by the Texas Scottish Rite Hospital for Children, a specialist limb centre.
These include the blades for running and 'stubbies' for sitting and playing.
Cody said: 'In my walking legs I can take big steps. In my running legs I can run very fast and jump on one leg.'
His mother added: 'They are very expensive and Cody seems to outgrow them all the time. We're very lucky that we have this specialist centre which provides the running legs.'
In return, Cody's family, friends and supporters compete in marathons to raise money for the hospital. They have so far raised £62,000 ($95,000).
Mrs McCasland and her husband Mike, 37, an internet manager, hope to bring Cody to London in 2012 so he can watch the Paralympics.
Cody's face is joyful as, clutching hands with mumTina McCasland and dad Mike McCasland he crosses the line at the Dallas White Rock Marathon
The determined seven-year-old, who is already gaining good times for his age range, said: 'I'd love to compete in three year's time at swimming.
'I definitely will take part one day and win a gold medal.'
When Cody, was diagnosed Sacral Agenesis, after being born six weeks prematurely, doctors had warned his parents that he might not live.
Children with the condition usually suffer from a number of difficulties including kidney problems and Cody had to undergo the first of his 15 operations at just three days old.
Over the next two years he faced operations for a dislocated hip, stomach, gall bladder and intestinal problems, a hernia, as well as treatment for breathing difficulties and asthma.
Mr and Mrs McCasland, who also have a daughter Callie, two, were warned by a specialist in Texas that Cody might need both lower legs amputated to give him the chance of walking with prosthetic legs.
Cody also enjoys fishing, along with his many other pastimes
Social worker Mrs McCasland said: 'He said the right leg was missing a tibia and knee cap.
'The fibula was not enough to support Cody's leg and without a knee, he could not bend it.
'His legs just curved round to the side when he was sitting and it just kind of got in his way.
'His left leg, looked more normal, but the knee did not bend. We were told there may be a chance of surgery to fix that leg but there was no guarantee of success.'
But thanks to his prosthetics, Cody takes part in activities with other children in his class and already beats some of them at running.
He is a member of his school swimming team, competing against able-bodied youngsters despite using just his arms.
One of the fastest seven-year-olds around: Cody running at the Endeavor games
Mr McCasland said: 'With the help of Challenged Athletes Foundation Cody will be able to travel to other areas and compete against others like himself at a higher level.
'Each year we take him to the Endeavour Games which is an international competition for children and adults with disabilities. He won gold medals in the 60m and 100m sprints this year and gained a fast enough time to enable him to compete in the National Junior Youth Disability Championships.'
Cody currently races against youngsters with just one artificial leg, but double amputees hope there will be a reclassification, allowing them to have their own category in the sport.
He ran 60m last year in 20.03 seconds, and 100m at 33.41 seconds, when he was just six years old. This means he was only five or six seconds behind single amputee record-holders aged nine.
Cody's times at freestyle swimming and back stroke are already impressive at around 30 seconds and 43.63 seconds. He has knocked 30 seconds off his freestyle time since starting swimming last June and is now only a short way behind the nine-year-old record holder.
He has already met his sporting hero, triathlete Rudy Garcia-Tolson, a double amputee who has competed in two Paralympics by the age of just 20.
The courageous youngster, who wants to become a doctor when he is older, said: 'I'm a non-stop runner and no-one can keep up with me.
'I'd also love to swim in a race against Michael Phelps or Rudy Garcia-Tolson one day.'
Cody's amazing achievements as a double amputee are inspiring numerous others from disabled children, to soldiers who have lost limbs in Afghanistan or Iraq.
'We receive lots of requests from people wanting to meet Cody,' revealed Mrs McCasland. 'It really is incredible to see this little boy walking up to grown men and telling them they can do all the things he does.
'Soldiers are just like big heroes to Cody, so he is so excited to meet them. And in a way he's a little hero to them too.'
The young athlete has even inspired the creation of Team Cody, a group of fundraisers who compete in marathons, already raising $95,000 for the Texas Scottish Rite Children's Hospital.
Team Cody has also raised $4,000 for the Challenge Athletes Foundation, which helps disabled sports people.