This item work via a transmitter which is in the shape of a battery smaller than a AAA. you then get 2 empty capsules , which are the shape of a AA size battery and a AAA size battery, the transmiter is inserted in to the apropriate size battery capsule to suit your remote control.
The Transmitter does need charging up and you charge it up by inserting it into the charging slot under the receiver. This is inconvenient and I am not sure how long the charge lasts yet.
The main issue with the device is that the transmitter and or receiver do not seem to be very good at sending the signal. Testing has been done behind walls on different floor levels etc. I just needed it to transmit from my bedroom to my living room, which is directly below. So in essence it had to go through floor boards and a ceiling.
Total distance from my bed to the receiver in the living room would be approx. 5 mtres with 1 floor in between. It just about does the job, I sometimes find that I have to use the remote close to the floor, which is not ideal. using it on a Second floor does not work at all, so if you have 2 floors and/or some walls in between, it may not work, particularly if they are brick/stone walls. not sure about studded walls, it may just do it.
I would give this item a 6 out of 10. Good for bungalows and cardboard houses (as oppose to solid stone build houses). one room to another on the same floor may also be ok.
I would recomend may be some of the other devices , such as the pyramids, with a proper transmitter, that you have to point the remote at. This way you dont have to worry about the transmitter battery running out and they seem to work better , possibly due to better transmission . I also have a set of SLX remote extenders and they work very well.