Can I use 2 sim cards in a single cell phone set?

Question

I have 2 sim cards of 2 different telecommunication company. That means i have 2 cell numbers., can i hold my cellphone as a multi card user set?

Answer 1

yes it is possible but you have to use the number in turn, they can't both be active at the same time.
there are two ways you can do this,
first with multiple simcard adapter that would look like this:
http://www.popcom.tv/www/content/view/31/49/1/1/
but this additional accessories is quite troublesome to use

second, with simcard copier or cloner that could store up to 12 numbers in one card, this is a lot better tool to use multiple numbers than the multiple card adaptor you also can use it to back up your simcard:
http://ucables.com/products/simcards/index.htm

Answer 2

i don't think so..
i think every cell phone only has one slot for one sim card.
so you can't put two sim cards into one cell phone.

Answer 3

Yes you can, though I have never tryed it, so I'm not sure how it works.

Answer 4

yes you can, you just need a special adaptor for it