Originally by: Amateratsu
What does Unprobeable mean
It means, that when your ship is not cloacked it can't be found(*) with combat probes, but appears on d-scan when in range (14AU).
Strategic Cruisers can pull it off easily with the Dissolution Sequencer Subsystem and still deal a lot of damage and are able to tank.
Other ships will be handicapped after you fit them 'unprobable'..
It usually involves stuff to bring your sig radius down (or at least not increase it) and also to bring your sensor strenght up.
Aim: sensor strenght/sig radius > 1.08
Stuff that helps:
Ganglinks when in Fleet (one brings sensor strenght up, the other sig radius down)
T3 with Dissolution Sequencer subsys
(*)no 100% scan result