Gunz, if you were running the V3 at 6v you were prolly using "high resistance" atomizers (3 - 3.5 ohms). The Legacy and most of the newer mods are using a single bigger battery now as there are some safety concerns regarding stacked batteries (2 RCR123a's). A single battery will put out 3.7 volts. The way to get similar performance from a 3.7V batteries is to run an atomizer that is less resistance, say 1.5 - 2 ohms. So, technically you have had to deal with ohms and amps you just didn't know it

You just called it an "HR atomizer" for my 6v device
Example: A 3.5ohm atomizer on a 6v device would be 10.28 watts of power being pushed to yer atomizer to vaporize juice. So, a 1.5ohm atomizer on a 3.7v device would be 9.12 watts. Don't worry too much about the numbers, the idea is that you try to create a setup that is similar to what you are used to and like. So, right out of the gate you could get a Legacy and a "low resistance" atomizer/cartomizer (1.5-ish ohms) and you would be rockin just like yer old device.
Now lets talk about the Kick. Over time any atomizer or cartomizer will tend to rise in resistance due to a lot of factors, dirty, crudded up, long use...... When the resistance rises on an atomizer, the batteries cannot deliver the same performance as it did when the atomizer was "fresh". Let's say that yer atomizer was getting old and rose to 4.5ohms, 4.5ohms at 6v is 8watts.......way lower than yer 10.28 you were happy with. make sense so far? Also the Prodigy is a 6v unregulated device meaning that the actual voltage of the batteries drops as they die down (ever notice how yer V3 "just wouldn't hit well" until you changed the batteries?) Realistically the V3 was putting out less than 6v for most of the battery life slowly decreasing until they needed to be charged.
ENTER the KICK!! The kick is described as a "Variable Wattage" device. The idea is that if you know you like 8.5watts to an atomizer (a V3 at a realistic 5.5v with a 3.5 ohm atomizer is 8.6watts) the you would set the Kick to 8.5 watts and the Kick would "regulate" the voltage output from the battery to maintain an even 8.5 watts. Pretty amazing right?!?! Well what does that mean to you without all the fancy numbers? This means that you put yer atomizer on the mod, set the Kick and the Kick Module will give you the exact same hit from your atomizer every time weather the battery is fresh or about to die AND weather yer atomizer is new or getting old. In a nutshell, the Kick takes takes a lot of the worry and thought out of getting a more advance, adjustable and customizable vape.
Now lets talk about "tanks". There are your common "cartomizer tanks". These are a clear tank that holds juice that you insert a disposable tank cartomizer into. The tank cartomizer has hoils in it that allow juice from the tank to soak into the cartomizer and allow you to vape a bunch before filling. These are pretty cheap, look cool and the cartomizers are pretty easy/cheap to replace once they die. They die just like any atomizer only a lil faster (that's why they are cheap) as they are design to be disposable.
Then there is a "rebuildable tank atomizer" like seen in my last 2 pics above(that is actually the same atomizer, one just has the metal tank section while the other pic has the clear). rebuildable tank atomizers have a tank section, a wick that drops into it and a positive and negative post that you connect a coil to that vaporizes juice(the working part of any atomizer/cartomizer) These types of atomizers have, up until recently, been kinda expensive and somewhat hard to get. With their fast growing popularity there are now some more inexpensive options available to people. Fair warning, these are relatively advanced atomizers that require some initial learning and understanding to get right but don't let that scare you away, once you have the idea and have used one you will have that "OH WOW!!!" feeling like you did when first starting vaping......at least most do

And you will save money buy not having to buy new atomizers all the time, you just wrap a new coil and be on yer way

The good news is that just about every rebuildable atomizer out there uses a 510 thread and can be used on the Legacy with issue.
Here is a pic of the coil on a tank atomizer (the same atomizer in the middle pic above):
and a pic of it making vapor:
There are many of that type of atomizer but like I said they are a bit advanced and can be overwhelming to some if they don't know what they are getting into. If interested in rebuildables, I would suggest starting out with something like the "Phoenix" ( the one in the top pic of my above post). It is super cheap (same price as 1 or 2 regular atomizers), pretty easy to rebuild and works really well. It would be considered a dripping rebuildable as it doesn't have a tank but it can hold about 10-12 drops before needing more juice.
pic of the Phoenix rebuildable wick and coil, when it was still on my Prodigy

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I highly recommend getting into rebuildablesas you can fine tune yer perfect vape and ultimately save some coin but be sure to do yer homework and research....there are tons on here that can help out with just about any question regarding the intricacies of rebuildables.
http://www.discountvapers.com/phoenix-rebuildable-atomizer-clone/
http://www.discountvapers.com/griffin-rebuildable-atomizer-tank/
this is similar to the tank atomizer I have up above. It is actually a cheaper made copy of a higher end atomizer called the DID mini. The performance is still really good and a good stepping stone before getting into the better quality stuff.
Since this is a Puresmoker section, I can't recommend the Legacy highly enough. They really did an amazing job and it is an awesome device. Trust me, if you love the V3 you will love the Legacy....prolly more
