Skivvy

The Skivvy was a beta vehicle that was cut from Grand Theft Auto V for unknown reasons.

Nothing remains of the vehicle, apart from unused police scanner files. According to the Skivvy's entry in the police scanner it was a speed boat. As its entry contains "hash_D4EC0C45" which ties it to "VEHICLE_CATEGORY_SPEED_BOAT_01" in the police scanner vehicle category.