Accessorize your favorite speaker system with this Amazon Echo Dot battery base. FEATURES: Accessory specially designed to work with Echo Dot (4th & 5th Gen). Echo Dot sold separately., Make your Echo Dot portable with the Mission Battery Base., Design blends elegantly with Echo Dot without compromising audio performance., Enjoy your music away from the power outlet with integrated battery lasting up to 5 hours. DETAILS: 14.17" H x 4.72" W x 4.72" L, Weight: 0.79 lbs., Uses 2 AA batteries (not included), Model no. B09RV39989; B09RV53551. Size: One Size. Color: Charcoal. Gender: unisex. Age Group: adult. Material: OTHER MATERIAL.