I have determined that two sub C Ni-Cd or Ni-MH cells will fit in a GloBee Fireplug in place of the 2 volt, 5Ah sealed lead acid cell. The sub C cells are also available in a variety of capacities, including 5Ah. It is not essential to have 5Ah, however. The capacity merely determines how often they will need to be charged. When wired in series two Sub C's put out 2.4 volts, which is easily tamed by the GloBee's standard rheostat. A pair of sub C's will cost less than $10, while a replacement lead acid cell will be at least $20. I also like the fact that Ni-Cd and Ni-MH batteries will peak charge with an appropriate charger, which I think will give them a longer service life. Try it next time your GloBee Fireplug needs a new battery. An added bonus racing pitmen will enjoy, this conversion takes 9 ounces off the weight of the stock unit.