1.2V Ni-Mh working?

I bought some 1.2V rechargeable AAA batteries for my pointers and only noticed when I got home that they are 1.2V. The little bit of paper that came with my laser says to use 1.5V.

Despite that, the 1.2s still work extremely well. So why is 2.4V working just as well as 3V batteries?

Have you measured them on a multimeter? Most Ni-MH:s are a lot above 1,2V in voltage when they are fully charged. I have such batteries from 3 different manufacturers and all of them holds about 1.4-1.45V when fully charged. As you can see, this makes the difference between rechageables and alkalines hardly noticeable.

Rechargeables also tend to hold their voltage longer than alkalines.