Loom bands are the talk of the playground.
But parents have now been warned about the dangers of the finger-weaving craze after loom bands injured two children.
In one case, seven-year-old Kyle Lawrence was injured when his older brother accidentally pinged a rubber bracelet into his eye, causing him to be temporarily blinded.
And in another, a young boy's fingers turned blue when he fell asleep with the small multi-coloured bands wrapped around his digits.
A GP has now urged parents to be vigilant about loom bands, the small multi-coloured elastic bands that children weave into jewellery with their fingers or on a plastic loom.
In the case of Kyle, from Cleethorpes, Lincolnshire, the boy had to be rushed to hospital after a loom band hit him in the eye.
The incident caused a blood clot - leaving him completely blind in his left eye - and Kyle is now awaiting surgery to restore his eyesight.
His mum Carlie said: "I will never have them in the house again. I emailed the company about changing the labelling to warn people but they haven't got back to me.
"There should be a warning on the packet - children shouldn't be doing the stretching. It's terrible that this has happened. I've had other parents come forward and say that something similar has happened, but not as bad."
The incident happened as Carlie sat with her children making bands known as 'rainbow loom sandals' which feature a band around the ankle with a strap which hooks around a toe.
One of them needed stretching to fit but as her eldest son pulled it the band slipped from his fingers and shot into Kyle's eye.
Carlie said: "He was screaming in pain and I have never heard him scream before. He started being violently sick.
"I couldn't go near Kyle after it happened, my husband had to deal with it. I was so scared.
"My husband told me to call an ambulance and we had to take Kyle out of the room to try and calm him down."
Kyle was rushed to accident and emergency, where he was examined before being sent home the same night with eye drops.
But after the schoolboy continued being sick throughout the night, Carlie took him back to hospital the next day.
An eye expert said he should never have been sent home and admitted Kyle for six days in hospital, and a further week's bed rest.
Kyle is now back at school but is unable to take part in any outdoor activities and is now awaiting an operation at Sheffield Hospital to try and regain the sight in his left eye.
In another case, a boy in Bristol fell asleep with the bands wrapped around his fingers.
His mum discovered his fingers were blue and removed the bands in time to restore his blood flow.
Now Dr Anne-Marie Houlder, a senior GP in Stafford, has warned that loom bands 'could be a choking hazard or cause circulatory problems if children swallow or wrap them round their fingers for any length of time'.
She added: "Parents need to be aware of the potential dangers if children are left unattended."
In addition to the health warning, some headteachers believe they're a nuisance and are increasingly banning pupils from bringing the bands to school.
There are reports they have been used as catapults in classrooms and led to playground disputes over copying designs.
But despite the warnings, the craze shows no sign of losing its appeal. In fact, this week, pupils at St Joseph's and St Teresa's School in Wells, Somerset, created an incredible 650 foot long chain containing 60,000 loom bands
They are hoping to break the world record the longest loom band chain - although they still have some way to go to beat the 29,040 foot chain created in California earlier this year.
Loom bands are the latest craze to sweep schools, following trends such as Tamagotchis, yo-yos, Furbys, pogs and Panini stickers.
Although they were only invented by an American engineer in 2011, loom bands are one of the biggest playground crazes of all time.
The Duchess of Cambridge is a fan and a few months after she was seen wearing the band, her parents Carole and Michael Middleton began selling a similar product through their mail-order company Party Pieces.