Works awesome. Holds 4 10mL bottles, fully assembled 510(maybe a little bit bigger model might fit), 4 attys with carts or drip tips, and 10 batteries. I obviously stuffed it just to see if it would fit it all. Also has an outside velcro pocket that you could put a sheet of blue foam in or just about anything else less than 1/4" thick. If you dont cram the insides ful, you can fit a usb charger and wall adapter in the outside pocket for on the go charging.