this is a better one than screwfix sell as its cheaper and also got the washer
http://www.toolstation.com/shop/Plumbin ... 697/p71736
look online or locally for a 15mm drill bit and just drill it out dont waste time filing it.
if there are enough people who dont want to or cant do that I may start to supply them for you at cost plus postage
pm if interested
Good price, and the washer is a nice thing to have too. I bought one just like this from Plumb Base or whatever it's called, it was a bit dearer than that.
However, the downside of this sort is the shape of the fitting where it is inside the vessel -- it doesn't have a hex bolt shape (two strange sticky-out bits of brass), so how are you expected to hold it still as you tighten it up? I don't really like it, but I'm only going to use mine it in situations where a tight seal isn't important -- like passing through the lid of something, etc... I used the washer to fit a Screwfix Flowflex tank connector to my boiler -- the right sized washers seem to be hard to find.
As for the 15mm drill bit, don't even think about bothering to DIY this unless you've got a pillar drill. I used one of the pillar drills at work.
Take it slow -- drill a very little depth, then remove the bit, go back in, repeat until you drill out the section you need to. If you don't do it like that, you'll probably end up having to hold the bit in a vice and pull the fitting off -- very tricky. I had to do that like 5 times when I was drilling the first one.
If you have only one to do, and don't either have the tools at home or work for the sort of technology firm that has 15mm drill bits and decent kit in the workshop -- a file does the job just fine.
