The FlexiShell Dash for iPod touch 4G is a soft, translucent TPU shell that lets you show off a limitless array of colorful dashes - in any pattern or arrangement you'd like! Here's how it works: The translucent TPU shell is designed with grooved lines on the inside of the case - we call them dashes, and they are arranged comparable to the style of a digital clock. We include a bag full of colorful lines that you can pop in place inside the grooves, in any arrangement of dashes that you like. The best part is, these dashes can be removed and rearranged as many times as you like - so you can change the look of your case as often as you want. The colored dashes are visible from the outside of the case, without poking through or falling out, so the back of the case remains smooth to the touch.