you can find more information in the page (I gave the link in the first post , this forum transforms links into " titles" containing hyperlinks automatically now)
and here you can find the brochure ( what follows here is the link)
"....
If water passes through the JoyKey, how can it possibly be airtight?
Magic?
No, science and a high-tec solution.
The high-tec WaterWick® metal filter is engineered to allow water to pass through but keep the tubing airtight under playing conditions. It also exploits the physics of water surface tension. A thin but sturdy film of water reliably seals the tubing against the air pressures that occur when playing.
In theory it is still possible to force air through the WaterWick, but it requires deliberate effort that is way outside of the playing situation....."
and here you can find the brochure ( what follows here is the link)
"....
If water passes through the JoyKey, how can it possibly be airtight?
Magic?
No, science and a high-tec solution.
The high-tec WaterWick® metal filter is engineered to allow water to pass through but keep the tubing airtight under playing conditions. It also exploits the physics of water surface tension. A thin but sturdy film of water reliably seals the tubing against the air pressures that occur when playing.
In theory it is still possible to force air through the WaterWick, but it requires deliberate effort that is way outside of the playing situation....."
, in the Netherlands marching bands ( the remaining ones we just lost the local one Tata Steel Harmonie) are certainly not allowed out now but there may be some places where they are still playing
