What's the difference between and ifor 505 & 505R?

[china]

I have just bought my first trailer it was advertised as a 505 but the chassis says 505R. Is there much difference between them? This is a 1999 model. Im very pleased with it, but I'm interested to know what the difference between them is?

 

[flirtygerty]

Our 505 also has an added R when we cleaned the frame, don't know if there is a difference but ours is a good trailer, very happy with it

 

[Jonesy]

I think it is just the model names at the time of production. Had a 505 (2002) which was known as HB505 double deluxe - but def no different to a 1999 trailer I previously owned, apart from partitions were straight sided rather than rounded.