This tiny cell phone got immense popularity among prison inmates, since it's easy to smuggle past the guards.

Just $ 40 gets convicted unit length of 72 mm and a genislik of 23 mm. It is made entirely of plastic and is not tracked by any metal detectors.

This is believed to be the world’s smallest phone – and there’s a not-all-that surprising reason why they’re proving popular with prison inmates.

The Zanco Fly is said to be the world’s smallest mobile phone – with a tiny 0.66 screen.

VIDEO: Worlds Smallest Phone!

It’s for this reason that prisoners are buying them from Amazon, and then hiding them inside themselves.

They’re proving pretty popular too, with one review stating that the phone is ‘very small and easy to hide’.

Another simply claims to have ‘put it up my butt with no problem.’

Former prison inmate Carl Cattermole, who created a guide to prison survival at, said that smuggled phones were ‘everywhere’ in prison.

He said: ‘Things like iPhones are rare in prison. Most phones go up a bum at some point or another, so f**k an iPhone 6 Plus, or, rather, don’t.

‘You’d look like Spongebob Squarepants: a rectangle with limbs hanging off. Having said that, I knew a dwarf who plugged a Blackberry.’

But the owner of a company selling the phones described the Fly model as ‘pretty good’ – but warned against sticking them up your backside.

He told Vice: ‘If someone rang me and said, “I’m going to put one of these up my a***hole,” I’d say don’t. I’ve heard of people saying they’ve had some of these small phones on charge and they’ve blown up.’

Technical Details

SIZE - 71.8mm*23.5mm*13.0mm