Loudspeaker for mobile, with base plate

Sound source for acoustics experiments
compact speaker for a mobile phone, tablet, or PC/notebook (also iPhone, iPad, iPod),

Control buttons for play/pause, volume, previous/next track, on/off switch; rugged grille guard for the speaker diaphragm; aluminium housing, metallic colour 
Cable for connecting to a mobile device and for charging the battery 
Device-shaped plastic base plate 
 
Technical data: 
Speaker: Da = 45 mm, 4 ohms, 3 watts 
Frequency range: approx. 40 – 11,000 Hz 
Audio input: USB, Bluetooth, memory card (Micro SD/TF card) and USB flash drive (both up to 32 GB) 
Supported audio formats: WAV/MP3/WMA etc. 
3.5 mm jack socket: for connecting headphones 
Playback time: approx. 8 – 9 h 
Battery charging time: approx. 3 – 4 h 
Power supply: lithium-ion battery, 3.7 V / 600 mAh, or 5 V DC plug-in power supply and USB cable (included) 
Speaker dimensions: 50 x 50 x 50 mm 
Base plate dimensions: 120 x 90 x 25 mm 
Speaker mass: 107 g 
Complete set mass: 159 g