Very useful accessory to bring the tube to the proper height.

my recent purchase of a Solar Quest head worked well with my Coronado PST but when I tried it with a long refractor it was clear that in the summer the refractor tube would get close to the Skywatcher tripod legs. Secondly it allows for more options for comfortable viewing heights. Very stable in use.
If like me you leave the Solar Quest tracking for long periods (sometimes unattended) the tracking mechanism might not survive if the scope fouls the tripod.

The extension tube is good and solid and I bought it to give clearance for my AZ Gti mount. However I could not work out what the thread was on the mounting hole. It says 3/8. I assumed this meant it needed a 3/8 UNC bolt to fasten to the tripod. But that doesn't seem to be the case. I tried a 3/8 UNC and a 3/8 UNF bolt neither of which fitted. Is it Whitworth or what? I'm assuming that the term 3/8 implied that it's not metric (say 10mm).
Anyway, I ended up using a 8mm bolt and wingnut to fasten it to my tripod and this works fine.

Fits on 3/8 skywatcher mount nicely don't have to extend legs on mount