Some folks ask, What's the blue thing? Is it a coaster? How do I use this thing? It's called a sidestand puck. You place it under you kickstand when you park your bike. This is particularly useful if you park in the dirt, grass, loose gravel or fresh tarmac. The sidestand puck will keep your kickstand clean and bike steady. It's free with your order and sure you can use it as a coaster, we won't say anything.