Where do I start? K looked around for castors wheels and being a first time buyer of castors wheels I was unsure where to go. RS Online is my go to site for such things, so inevitably it was my first port of call. And as always they had what I was looking for. But being a savvy buyer I went on a web crawl to see if there is any other sellers of castors. I found a few none of which had what I was looking for. Then I found Ross Handlings and I'm so glad I did. As with RS Online, Ross Handlings were the only sellers that could supply M10 25mm threaded stem swivel castors. Both of which were identical. Only difference was RS Online's was colour coordinated and being sold as high end furniture castors at an extortionate price, while at Ross the price was affordable, not only that they could hold more kg. So a bargain and having installed them I'm just speechless how well they perform under load. I used the base in the photo as a skate board just for kicks, before attaching it to the rest of the structure, it was so much fun and works so well. I castor crazy. I see them every where. Yea go Ross Handlings for castors. Won't be going anywhere. Quality assured. 5 stars.