Red Ring

Red Rings also known as Red Coin Rings are objects present in New Super Mario Bros. and New Super Mario Bros. Wii, that when jumped through it will make eight Red Coins appear. If all Red Coins are collected, then the player receives an item depending which form Mario is in.
 * For Standard Mario and Mini Mario, a Super Mushroom will appear.
 * For Super Mario, a Fire Flower will appear.
 * For Fire Mario, Shell Mario, Ice Mario, Propeller Mario and Penguin Mario, a 1-Up Mushroom will appear.

In New Super Mario Bros. Wii, a Fire Flower is awarded if Mario is in his standard form.