Since quite a few folks are venturing into Tankland, the issue of replacement Dual Cartos is just around the corner.
Here is a quick reference to use, remember flanged Cartos are the best way to go for tanks:
1.5 Ohm Dual Cartomizer..............3.7v Devices
2.0 Ohm Dual Cartomizer...............5v Devices
2.5 Ohm Dual Cartomizer...............6v Devices
3.0 Ohm Dual Cartomizer...............7v Devices
Like everything there can be a little bleed over, however variations in device voltages, especially anything higher than a 3.7v device can make certain juices go from awesome to blech.

Here is a quick reference to use, remember flanged Cartos are the best way to go for tanks:
1.5 Ohm Dual Cartomizer..............3.7v Devices
2.0 Ohm Dual Cartomizer...............5v Devices
2.5 Ohm Dual Cartomizer...............6v Devices
3.0 Ohm Dual Cartomizer...............7v Devices
Like everything there can be a little bleed over, however variations in device voltages, especially anything higher than a 3.7v device can make certain juices go from awesome to blech.
