I saw Arunas answer...He said he couldn't find any notice about this model but the caption of the quiz picture, so I spent some time trying to know something more about Belsize's history. On the net there's very little about this maker, and so on my books, but, as I told, it seems that Belsize stopped to produce cars in 1925 and since 1922 its cars were sold as Belsize-Bradshow. I understand that RM6 could be the name of one of the new products Belsize meant to produce before it went into bankrupt and they weren't actually realized, according to Georgano. So, is this a very rare / unique prototype, or is the caption / Georgano not reliable?