This is a British Distribution company based in Stanley, County Durham whose name is often abbreviated to RUMC and whose house brand is Clearwater. It was founded in 2001 and sells mainly online through Amazon, eBay and the like though I have seen them on sale in shops too. They distribute a range of Instruments including wind and percussion as well as chordophones like Guitars, Mandolins and Ukuleles. 

I have seen Soprano, Concert, Tenor and Baritone Ukuleles branded by them but never long neck variants and never extra string variants. One thing they appear to do, and I have never worked out if they are seconds or not, is have a selection that is from the same Chinese maker and a more international brand, so in 2011 they had a number of models that were identical to some of Ohana's and in 2012 it was Eleuke they were mimicking? In 2013 the main new Ukulele model by Clearwater was the ABS plastic Concert made by Lanyao.

Although they still advertise some of the "copy" ranges from the past they do seem to now be more of an online reseller for other British and European brands.