The Standard MR is one of Mario's three karts in Mario Kart DS, the other two being the B Dasher and the Shooting Star. It is just like all the other Standards in build and design, the only difference being the color, which is red. Mario's big red "M" is on the front of the kart unless the player has an emblem. It is an all-around kart, with all stats being average, and nothing being poor or great.
This kart is very famous, though, appearing on the title screen with Mario on it. Mario is always seen riding this kart in the demo movies that play when the racer waits too long to do anything.