The above model of mp3 player (Serial no.M13CBMC3111785A)is giving very less battery backup. I have been cheated by the company as they didn't mention the battery backup of the device on the packing. I thought it should be up to 10 hours as all other mp3 players give (even china made products give that long backup) but this Moserbaer product gives only 3 hour battery backup. The company is lacking far behind in technology so they didn't mention that the product will give backup of merely 3 hours. All specifications of the product should be mentioned on the product like backup etc.