As we try to provide adapters that are secure and will stay on after attaching, the adapters to be a bit stiff at first use. However, we have done multiple quality checks and confirmed that all adapters (EU, AU, and UK) do fit on both EU and US plugs. 

 

To complete successful insertion of the plug into the adapter, please apply steady force between the two pieces. While some customers may be concerned that the application of pressure may cause one or both pieces to break, we encourage giving the the plug a hard push into the adapter. This should cause the plug to snap into 

the adapter. 

 

We ask that you please try again to put together the two pieces as instructed above. If you are still not successful, please email Customer Care at "support@numestyle.freshdesk.com" for further assistance.