It looks like a lot of parts but you don't use them all at once.
You have 2
batteries and 7 clearomizers. You'll only use 1 battery and 1 clearomizer at a time. Or 2 and 2 if your husband wants to try it.
You fill the clearomizer and simply
thread it on to the top of the battery.
eGo
batteries have larger threads on the outside (eGo threading) and smaller threads on the inside (510 threads). With clearos that have 510 threads, the Vivi Nova for example, you can use the eGo Thread Cover on the battery before attaching the clearomizer. It is not necessary, just cosmetic. In some cases it will help support the clearo.
SR and LR heads are
Standard and
Low
Resistance heads or more specifically the coil of wire in the head. Lower resistance and higher voltage from your twist will heat the head faster and hotter. Remember Ohm's law, I = V/R?
Skip to the bottom for a refresher course.
You'll have to experiment with what you like best.
You have plenty of hardware for both you and hubby to get started.
My wife thought she was happy with just an eCig device until I got an eGo passthrough battery and clearomizer. Now she wants to use it all of the time. I'm fine with that. It just gives me a reason to order more stuff to try. I ordered a mini eGo battery and an EVOD clearomizer for a stealthy setup for myself at work.
Ohm's law, vapers edition.
Current (I) amperage = Voltage divided by Resistance. So if your twist is set at 3.2 (V)olts using a 2.0 ohm (R) coil (head) the current is 3.2/2.0 = 1.6 Amps. If you set the twist at 4.0 Volts and use a 2.5 ohm coil you have the same result, 4.0/2.5 = 1.6 Amps.
Standard eGo batteries are rated at 3.7 Volts (actual is lower) and most standard clearomizers are about 2.8 ohm. 3.7/2.8 = 1.32, obviously lower than 1.6. The higher the amperage the shorter the life of the coil.
A 650 mAh battery means it will supply 6.5 amp hours of use. 1 amp = 100 milliamps. If you have your device using 1.6 amps on a 650 mAh battery you should get 4+ hours of use.
Sorry about the school lesson on a Sunday.