base 5 hex 'visible' range, (modified by sensors, and things that alter sensors like probes, etc.) weapons may not lock, but science abilities can, and tractor beams/gravity well can pull you out.
No decloak bonuses to the attack.
weapons, shields and Aux go to 5 while it's active-same restrictions as normal cloak regarding shields.
+25 to Threat Control on decloaking.
base .2 % cumulative chance of exploding or causing other system failures. (Fed ships aren't designed to cloak-the console cloaks are installations from a knowledgeable 3rd party contractor. witness the results of FEderation attempts to develop cloaking systems independently-all have ended in lots of dead starfleet crewmen and lost ships.) chance resets at 98%.
"when you're out of Birds of Prey, you're out of ships."