Can someone help me with sizing pics included

[Confusedmind24]

I'm looking at this coat. But I don't understand the sizing . I have included screen shots of the sizes and size guide.

The sizes available are the chest measurement, so a 40r is a medium, a 42r is a large etc.

Yes, it is confusing because normally R is for trouser length meaning regular.

I would go with what @Kickingasssince72 has said.