Child car seats that are illegal to use in the UKare available to buy from eBay, Amazon and AliExpress, despite repeated warnings from Trading Standards and Which?.
The seats, which sell for as little as £8 and are made of fabric, could be potentially deadly if involved in a car crash.
Surrey Trading Standards first warned about these types of car seats in 2014, dubbing them 'killer car seats' and pushed for them to be removed from sale.
Just over a year later, we've spotted the same types of car seats available on eBay, Amazon and AliExpress.
Surrey Trading Standards dubbed these car seats 'killers' for good reason.
When car seat manufacturer Britax used one to show the effect of an impact when travelling at 30mph, the test dummy, which represented a three-year-old child, was flung through the windscreen when the straps securing the seat came loose.
If this had been a real child, it could have resulted in life-threatening injuries.
Watch what happened in that crash test and find out more about why these seats are unsafe by watching our video below.
Our investigation found:
The law on child car seats states that only EU-approved seats can be used in the UK. These will have a clear orange approval label indicating they can be sold in the UK market.
The fabric car seat we bought on eBay lacked any form of labelling.
If you need to buy a baby or child car seat, follow these tips:
eBay has since removed the listing for the fabric car seat we bought, as well as other listings for products that we highlighted as being similar.
eBay has contacted all the sellers involved and requested they contact the buyers to organise a return and to pay for the return shipping.
A spokesperson for eBay said: 'The safety of our customers is paramount and we do not tolerate the listing of non-compliant items by sellers.
'Our specialist teams work with regulators and Trading Standards to ensure our block filters stay up to date, using sophisticated software that monitors billions of listings a day to remove any prohibited items.'
Amazon has alsoremoved the listings we alerted it to and has contacted customers who purchased from them.
A spokesperson for Amazon said: 'All sellers must follow our selling guidelines and those who don't will be subject to action including potential removal of their account.
'The products in question are no longer available.'
AliExpress has removed the listings we highlighted. It told us: 'AliExpress considers the safety of all our customers, especially children, to be of paramount importance.
'AliExpress operates a third-party marketplace where individual merchants and manufacturers sell goods directly to consumers. We prohibit the sale of products in contravention of the Product Listing Policy of AliExpress and we have policies and procedures in place to help us identify listings which infringe the policies of our online marketplace by third-party sellers.
The company also confirmed that in its returns policy, third-party sellers are required to provide a returns and refunds guarantee to buyers which provides customers with the right to return the product within 14 days of purchase if the product is not as described or is of low quality.
Alex Neill, managing director of Which? home products, said: 'Parents will be horrified at the thought they could be unwittingly putting their child's life at risk with one of these 'killer' car seats. Online marketplaces cannot continue to turn a blind eye to dangerous and illegal products being sold on their sites.
'The UK's product safety regime is in dire need of reform. More needs to be done by big businesses and Government to protect consumers from dangerous products.'
Any customers that have bought one of these fabric car seats should stop using it immediately and return it, as it's not fit for purpose as required by the Consumer Rights Act.