One easy way to conceal the explosive would be to overmold it in a cavity inside the plastic enclosure. This would escape all but the most thorough inspections.

One easy way to conceal the explosive would be to overmold it in a cavity inside the plastic enclosure. This would escape all but the most thorough inspections. And since battery terminals are typically also embedded in the plastic this can provide a clandestine supply of power and signal with something like Dallas protocol to the fuse.