In this video I'm showing a 3D printed telescopic whistle with a blues scale made by TeleTunes in Finland.

This instrument is available from Etsy: https://www.etsy.com/shop/teletunes

As always, you can find the subtitles (und eine deutsche Übersetzung) in my blog: https://andijah.eu/index.php/2025/07/24/subtitles-untertitel-teletunes-blue/