He could easily sit in the palm of a hand but he is probably worth his weight in gold.
His name is Diego and he is a golden lion tamarin born at Bristol Zoo Gardens.
Diego is precious because he is contributing to an important conservation breeding program to save these charismatic monkeys.
They are endangered in their native South America because their forest habitat is being destroyed.
At the moment Diego is still being carried around his home at the Zoo by his mum Missy and dad Dourado.
It is the first time they have become parents and staff at the 180-year-old Zoo in Clifton say they are coping very well.
And Diego is already showing signs of wanting to explore the world on his own.
Mammals team leader Sarah Gedman said: “We haven’t bred golden lion tamarins at the Zoo for a few years so Diego is the start of a new generation here at Bristol.”
Diego, who is just 10cm (4 inches) long, is still suckling but he has started nibbling at sweet potato and sweetcorn.
Golden lion tamarins take their name from their impressive manes which are smaller but similar to those of fully grown lions.
They live mainly in trees foraging by day and eating fruit, tree gum and insects.
But Brazil's Atlantic coastal rain forests, where they live in the wild, are disappearing due to logging, agriculture and industry putting the future of golden lion tamarins at risk.
It is estimated there are just 3,500 of them left in the wild.
Bristol Zoo Gardens is a conservation and education charity and relies on the generous support of the public not only to fund its important work in the zoo, but also its vital conservation and research projects spanning five continents.