Having arthritic thumbs meant I was having a lot of trouble getting a good seal on the lid due to the amount of torque required with nylon inserts fitted to the supplied nuts/knobs.
I was going to use a set I'd got for my Thumblers but these turned out to be a different thread pitch. Having emailed Jon he got in touch with the manufacturer and I've just received a pack of 6 without the nylon inserts, what a huge difference!, I just put them on finger tight and it seals beautifully :)
So, once again, Thank You Jon party2