Timer yukkuri!

The Green Switch is an Japan-exclusive e-Reader card that is used with Super Mario Advance 4: Super Mario Bros. 3. It was included in the Series 2 set of cards. It can be used in both the main game and in World-e.

Once this card gets scanned, the timer and music slow down for the first 50 counts, giving the player more time to complete a level. When 50 counts are past, the "coin" sound is played and the timer and music go back to their original speeds.

Japanese
タイマーゆっくり!

Translation
Makes the timer go slow!