Flat spline

Have you ever seen a puzzle with curved pieces that fit together perfectly? Well, a flat spline is kind of like one of those puzzle pieces - it's a long, thin strip of material that can bend and flex in different directions.

A lot of times, flat splines are used in things like windows or doors. You know that little groove that runs along the edge of the window or door frame? That's where the flat spline fits in! It helps to hold the glass or screen in place by wrapping around the edge and pressing it against the frame.

Flat splines can be made out of lots of different materials - like rubber, vinyl, or even metal. And because they're flat and flexible, they can be cut to different lengths and shapes to fit perfectly wherever they're needed.