Keep vaping all night long! The Efest LUC V4 4-bay charger has enough bays to charge two full sets of your dual-battery box mod batteries at once!
Large, detailed screens for each bay keep you posted on charge rate and battery voltage. The springs are made of piano-wire, and are smooth like butter; they provide correct tension for a broad array of compatible batteries (see below).
The LUC V4 can charge four batteries at 0.5A or 1.0A, or two batteries at a full 2A charge rate. You'll get the kind of protection you expect from Efest, with over-discharge, over-voltage, short-circuit, and reverse polarity protection built in. It can even activate batteries whose charge has fallen below 0.6V. It'll automatically stop charging when your batteries are full, and will automatically start charging any battery that's reached less than 4.1V.
The Efest LUC V4 includes both a US-standard wall plug and a car adapter. (Put that cigarette lighter to good use!) It also includes a USB-out port, so you can charge your USB-chargeable mods (and your phone, for that matter) from it, as well.