It's only as good as it looks!

Finally... The dimensions of the final product are as follows:

• Length : 60mm (55mm is possible)

• Width : 36mm 

• Height : 32mm (27mm might be a possibility) 

With this prototype in mind, the actual size of the PCB can be finalized. 

• PCB size : 34mm X 53mm (maximum!) with a height of 10mm (a maximum of 12mm can be arranged!)

Note that the major concern of these dimensions happens to be the height, at least, as at now... 

A word about the marketing angle:

The SIP happens to be a portable charger. No matter where you are, you should be able to use it. The main reason behind not using AAA batteries happens to be this same concern. (The availability factor of AA batteries is much higher in comparison with AAA batteries [at least in SL].) Therefore, our main goal should be to focus on those who travel, preferably on a regular basis. Most of the travellers have at least a single set of keys with them. Since the dimensions seem to be appropriate, marketing this charger as a charger + key tag would be an advantage.

The marketability of the product heavily depends on the design of the casing, so, sure this'll be one of the most challenging phases of the whole project..