The Bottle Marimba is a beautiful little instrument that is so much more than meets the eye. Made out of recycled materials, it produces a wonderfully pure resonance. It is so cheap to build and so easy to construct, and I really hope you give it a go.

Josh and Cat from Kaboom Percussion built an amazing version you can see here:
   • Disney Medley on Plastic Bottles  
(BTS)    • Disney Medley Behind The Scenes - PLA...  

Within the contemporary music scene, the flexible tuning of the instrument allows for fascinating timbral possibilities. Check out a piece I wrote and performed in my 2018 graduation recital here:
   • Jet Kye Chong - Recital 2018  

The bicycle valves I used were TR414 valves:
https://www.ebay.com.au/itm/10x-TR414...
Most should work just fine. Even better if you can recycle an old bike inner tube.