lucy24 - 10:36 pm on Feb 26, 2013 (gmt 0)

I want to know if it gives longer usage.

Heh. When I saw the topic header I couldn't figure out if it meant physically stretchy, or a variable lifespan. It serves up only the amount of power you need, and its lifespan depends on power consumption rather than elapsed time. Like a rubber band that gets skinnier when you stretch it.