Bob's nailed it with the info above.
Even better yet, RIO, and probably why I have so many of their lines and other goodies, is the only manufacture I know who will actually take the time to talk to you about YOUR specific needs.
Simon is a true gem! I've had several occations to contact him on where/what of their products to purchase (last one was for their new sinking leaders). Not only did he research with RIO's marketing dept on whose stocking them, but sent me the phone number(s).
Leaders are on their way to me now from Creekside Angler's in Salem, OR. (And yes, I did recommend they come to "our" web site with an eye to advertising.)
The point to this is: "There is customer service, and there is customer SERVICE.'' Huge bow from the waist to the folks at RIO for not only doing it right, but continuing to do it right over the years. Suspect their management has long since learned that 'new customers are silver, repeat customers are gold. There is no better advertising that a truely satisfied customer. As an example of this from about 3 years back I purchased an Alrtr. line from a Washington retailer. Specificly (sp?) told him the line was for Spey rod use; "No Problem." Like ya, when I got the line. And he wouldn't/couldn't replace the line with the correct product ......
Called RIO to see if they could help on a 'swap.' New/correct line was in the mail to me and on my desk about 4 business days later.
fae