The product comes with a small screwdriver to remove the battery covers (helpful) however, the screws get stripped almost immediately, no matter how slow and careful you are.
The screws are also far too stiff and long, it took a solid two full minutes to carefully get just one cover off. The final one I think the screw was already stripped it barely turned and the screwdriver just spun, I had to just break the plastic cover off to get access to where the batteries go.
As these have no on/off switch the batteries would need to be removed after every use and then put back in when you want to use them. The buttons work perfectly but are very sensitive and would be going off constantly with travel, even in their box, the lightest tap of the box and they were already going off inside. So obviously this would be annoying and drain the batteries.
It's a bizarre design to make near impossible to get into battery compartments on a product that has no on/off and needs the batteries taken in and out regularly.
Fortunately the batteries fit snug enough that they won't need the covers (hence why I just snapped the last one off instead of returning). A piece of electric tape over top of them will also do the trick to ensure they stay in.
All in all, the buttons work and are fun but for the price I would have expected a slightly more intelligent design where the batteries are concerned. A simple snap on and snap off cover would have sufficed instead of screws that don't work.