Wave Form Helix with Wooden Stand - 20cm

The helix is a metal slinky spring that stretches for demonstrating wave forms, and can be used on stairs with a tall step height for further experimentation. It measures 20.0cm (H) when compressed, and has a wooden stand for display and storage. (H is height, the vertical distance from the lowest to highest point.) The helix is suitable for high school or college students, or ages 14 to 21.
Helix will extend up to 65ft before distorting.