The Sansa Shaker was SanDisk's attempt to capture the pre-teen PMP market with a fun, unique design utilizing twist controls for volume and track selection and random song selection via shaking the unit. Somewhat unheard of at the time of its release, the Shaker also featured a top mounted speaker for play sans headphones and dual 3.5mm jacks for sharing with a friend. The Shaker used SD cards (up to 512MB) as its storage media and ran on a single AAA battery for up to ten hours.