I think it's such a great idea, Geoff, I've been researching it for about an hour. It's not available for shipping from the US and shipped from the UK costs about $25. That gets you the one tool.So, looking at the same type tools in the US, and doing a bit of research on quality, I came up with this alternative for about $26 shipped:https://www.expressions-ltd.com/ProductDetails.asp?ProductCode=CAULKING%2DBALL%2DTOOL&CartID=1This gets you 8 different sizes. What got me going on it is that I've wanted something like this for better results on caulking and grouting.