Seeing this a Riot Helmet for sale on Ebay reminded me of how much I really liked the fit and protection of the similar Riot Helmet I owned for several years.
Here is what I said about the Riot Helmets at the time I was using one:
The Riot helmet is no longer produced and has been quite difficult to get hold of. They came in two varieties the R1 and R2. Shell sizes are standard with the amount of inner foam being the deciding factor on size.
Both helmets are fitted with standard foam outfitting with additional foam 3 or 5mm sticky back foam added to gain the correct fit for the paddler. In addition both helmets have been fitted with a set of nose clips.
These helmets have always been difficult ot order and since the end of production this has made the situation worse. However check out some online U.S sites as most dealers will export them to the UK.