Difference between these two Panasonic 18650 3400mAh ?

Thanks for the informative links Calmaja. The length does seem to be a concern. Was eyeing on this Keeppower 18650 3400mAh, but noticed that the cell was reported to be too long for SC600 (as an example). Sounds a bit scary, for someone who has been trying to get a foot into the Li-Ion world. :wink: