The adjustable rest and strap loop are handy, and it's just two screws to fit it, which is super easy if you have a hand micro drill set.
Sadly the part could be better finished - although the outside is perfectly nice when fitted, the screws need to be pre-fitted in their countersunk holes before attempting to mount it on the instrument. The tiny holes are a little tight and when the screws bounce off their holes you'll probably drop them.
The adjustment screw needs to be very tight but there isn't a lot of space to fit a tool next to it when tightening. It seems like a coin slot rather than a screwdriver slot. I ended up using the handle of some tweezers to get it tight. So not super convenient for adjustment. Allen key adjustment would be better. The base screws (into my plastic clarinet) tend to come loose quickly too, and will need something like loctite to fix. I think three screws would be more stable.
At £17 you just get the part in a bag, with the screws and a 13mm circle of 1mm cork. It doesn't feel like £17 worth. But then, in clarinet world, it is cheap compared to the alternatives.
I didn't use the cork and instead fitted a B&G rubber on the end.
It is pretty comfortable in my limited experience. A worthwhile upgrade. Bear in mind it uses two screws spaced horizontally ~10.5mm center-to-center. You may need to drill or have someone fit it for you if different from your current setup.
