Electronics noob needs help ....

Ok so I dont know my amp from my *** so please be gentle.
I use two primary 123a lithium batteries with my Surefire 6P LED. I would like to test them with a battery tester to check voltage of each battery to make sure that they match for safe use.
Does anyone know how much difference there can be in voltage between the batteries for safe use to occur. I ask since I am aware the one of the main risks with 123a batteries in multi-cell lights is one cell full, one cell empty = poof .....

Also is there a risk if depleted below a certain voltage and what would happen ?

I don't think there is an issue with depleting primary CR123's (as opposed to rechargeable li-ions). As far as matching just put new ones in and there will be no problem.

If you've done that you don't need to continue testing them. If you have partially used batteries laying around the house and want to put them in a (2) Cr123 light I wouldn't do it unless they were both new. Just save those for single applications.

If there is a specific voltage answer to your question I'm sure someone will respond.

Thanks Im still learning all the time, just want to be safe ......

I think pure voltage readings on CR123A cells can be misleading. For better results you need to use a battery tester like the ZTS that is often talked about round these parts.

But even so, the advice stands. Buy reputable brands, put a pair of brand new cells in the light, and do not mix and match old or partially used cells.

Thanks Mr Happy, I will look into the tester you speak of ....