Bandai Ben 10 Omnitrix F/X Wristband | With flashing red and green lights, and transformation sound effects taken directly from the TV series, the OMNITRIX F/X provides the ultimate role play experience! Like Ben's watch, the OMNITRIX F/X will signal activation and de-activation with cool lights and sound effects. The aliens' silhouettes can be seen on the face of the watch and are backlit for an easier view. Turn the dial and select an alien! Requires 1 CR-2032 battery (battery included). For ages 4 years and up.