The Pick Nails are a pair of small heart shaped shovel attachments that is put on the toes of Rouge's boots. They only difference between Rouge's normal footwear and the Pick Nails is a small, pink and grey strip along the toe of each boot. Once equipped, the Pick Nails allows Rouge to perform Dig in order to find hidden objects. They are the equivalent to Knuckles the Echidna's Shovel Claws.
In Sonic Adventure 2 and its enhanced port Sonic Adventure 2: Battle, the Pick Nails are located in the Egg Quarters and are needed to get the final key and complete the stage. They can be found in the Egg Fish Chamber, one of the three main rooms in the stage which is noticeable with the light shade of blue the room has and the fish statue on the wall.
Inside the Egg Fish Chamber, the player will see a room with cages blocking the doorway on the higher platform. They must use the missile found on the smaller platform in front of the doorway to destroy the cages and head inside the newly revealed room. The player can then find the Pick Nails in the back of the room.