They have the 808 ce2 cartos that fit right on the v4l
batteries. And yeah they have the 501 to 808 adapters and vice versa. I bought some 1050 mah ego elegant
batteries 510 models that are good for like 8-10 hours chain
vaping and the e-power is the one that lasts all day and most of the next. Also you want to try the sapphire bud carto. It's really easy to use. I just prefer the hits off of the ce2.
Lmk if you need any help cuz some of the new lingo they have can be somewhat confusing. The have a vendor section on ecf with videos there that can be helpful as well.