the boston marathon, components of the bombs arrived very quickly here at the lab. and explosive residue was tested right here. here is the evidence from the underwear bomber. after analyzing it, the lab quickly warned this was a bomb with no metal parts, hard to detect at airports. for the first time, you see fingerprint technicians, scoured phone parts. food remnants. >> how often are you able to recover a print that's good enough to look for a match. >> approximately 60% of the time. >> reporter: details that have helped the lab identify terrorists from around the world. but budget cuts are on the horizon. they just hope the team will be here for the boxes that are certain to keep coming.