Here are a number of Hardshell Underseat Bags suitable for use on Ryanair and other Low-Cost airlines. If you are looking specifically for a Ryanair compatible bag then make sure it has the following dimensions.
40x20x25cm
Hardshell Underseat Bags
More on Underseat Bags
If you are looking for more information and options on Underseat bags then check out our quick read guide.