Acrylic Big Belly Drip Tips
Def try the Big-Belly Drip tips. Hoosier sells them for only $1.99 each, but other vendors like CCV, Madvapes, etc also sell them.
I really like them and they are the only cartos I use on my tanks. They fit really snug so they wont wiggle and fall off, or fall off if the tank slides up.
I have 2 Smoktech 3.5ml tanks and Ive never had either leak the slightest bit and I carry both of them in my pocket everywhere I go. I use the Ressurector cartos in my tanks that have a metal base on them which stops the tank from being able to slide down. With the metal based cartos and a big belly drip tip, the tank cant slide up or down and I can carry them in my pockets without worry.
Heres what the big belly drip tips look like on a tank:

Its kind of hard to see it in the picture, but the bottom of them are slightly fatter than the carto and thats what stops the tank from sliding up. The second picture is a big-belly drip tip on a Ressurector carto by itself, and you can see the shape of the drip tips alittle better.