808 cartos aren't compatible with 510 batteries unless you use an adapter. Drew sells 510 cartomizers that have 510 threads...yes I know they are basically an 808 with different threading on the connector, LOL. Sorry I assumed these were what you were referring to since you said they are compatible with 510 batteries.
The 510 cartomizers Drew sells go directly onto a 510 battery and have the soft tip.
The 510 cartomizers Drew sells go directly onto a 510 battery and have the soft tip.