So, a couple of friends of mine recently purchased the eGo passthrough batteries, mainly for the convenience of charging while vaping. One of the asked me the other day why his button had changed from blue to an orange color. I had no idea, but found his "instructions" from his box and found out that there were two different settings available on this battery. One is a constant voltage, and the other is a variable voltage. This variable voltage setting is not user defined like on a vv type PV, so what is the story with that setting? I put instructions in quotation marks earlier because the instructions tell you how to change from one setting to the other, but not what the purpose of either one is. To a newbie this can be very confusing. A BIG thumbs down to the local brick and mortar that sold these devices for not explaining this to their customers. I use a standard 510 eGo 900 mah for daily use and a new vmax for at home so I get the variable voltage (I actually use the vw option) on my vmax, but not this "oddball" vv of the ego passthrough. Detailed help so I can help these friends decide how to best utilize their device would be very helpful. Thanks.