Vox Amplug 2 BASS Portable Guitar Amplifier Overview:

With amPlug 2, the crucial analog circuit has been drastically improved, and each model now provides three modes. Guitar types provide multi-effect functionality, and a rhythm function has been added to the bass type. A foldable plug mechanism that rotates 180 degrees and an auto power-off function are additional features that contribute significantly to improved convenience and ease of use.
The amPlug is the simplest way to get serious sound; occupying virtually no space, it's an ideal choice for any guitarist or bassist.

Bass: Designed specifically for low frequencies, offering a wide-range response.

Specifications:

Connections: Headphone Out, AUX In
Power Supply: AAA batteries x 2 
Battery Life: 
11 hours (With alkaline batteries, RHYTHM on)
17 hours (With alkaline batteries, RHYTHM off)
4 hours (With zinc-carbon batteries, RHYTHM on)
9 hours (With zinc-carbon batteries, RHYTHM off)

Dimensions: (W x D x H): 86 x 38 x 31 mm / 3.39” x 1.50” x 1.22” (with the plugh in the storage position)

Weight: 40 g / 1.41 oz. (excluding batteries)

Accessories: AAA alkaline Batteries x 2 (For verifying functionality)