Made of brass Diameter: 5mm Side: 6cm Suitable as an ornament or keychain. When making triangles, I experimented with several small sizes to investigate the tonal characteristics. I am offering for sale those that had a decent tone. Please check the sound at the following URL: https://youtube.com/shorts/aScMP-01lIo?si=tGjoCs6hMtzjwjcC Please note that this is a very small triangle. It's difficult to tell in the video, but the volume is very low. It's not a volume suitable for ensemble playing, so please be aware.