Does anyone know if this will work backwards? meaning multiple input devices (i.e. tv and mp3 player and/or cellphone) and then 1 output to speakers?

Absolutely this will work as a passive mixer. I bought this to do exactly that. I can run 5 instruments at a time to one speaker output. What's even more interesting is that the signal can work both ways simultaneously. Meaning I can actually have like 4 inputs and 2 outputs... or 2 inputs and 4 outputs, if I wanted something like that.

Does the usage of battery go up when there's more then One plugged in ??

Not that I saw. We used it with an iPad once and a laptop another time to watch movies. If the artery consumption increased, then it was minimal to the point that I did not notice.

ASIN	B00904WS2K
Best Sellers Rank	#10,201 in Electronics ( See Top 100 in Electronics ) #216 in Headphone Adapters
Customer Reviews	4.6 4.6 out of 5 stars (7,312)
Date First Available	July 2, 2004
Department	Unisex-Adult
Is Discontinued By Manufacturer	No
Item Weight	1.12 ounces
Item model number	F8Z274bt
Manufacturer	Belkin Inc.
Product Dimensions	24 x 2.46 x 0.54 inches

F8Z274BT-PUR ROCKSTAR Multi Headphone Splitter- PURPLE

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