It'll soon be harder than ever for criminals to produce counterfeit $100 bills. That's because a redesigned Benjamin Franklin that's been in production for quite some time is finally entering circulation today courtesy of the Federal Reserve Board - one of the few government agencies that wasn't affected by the ongoing US government shutdown.

The Federal Reserve has been working on the redesign for more than 10 years. Described as the most complex bills the US has ever produced, the design was first unveiled in 2010 but delays kept it from reaching production until just recently. That's unfortunate as the $100 bill is the most counterfeited note outside of the US, we're told.

The new bills are equipped with a number of security features. Chief among them is a blue 3D security ribbon that will change from images of a bell to "100s" when moved. The ribbon is woven directly into the paper, not printed on it, which will make it easy for people to identify and verify but extremely difficult to replicate.

Other security features include a green bell inside a copper-colored inkwell on the front of the note. When the bill is handled, the bell will change from green to copper to match the inkwell.

Not all of the technology on the new currency is unique, however. Many features, including the portrait watermark, color-shifting 100, raised printing, security thread, gold 100 and serial numbers are all carried over from the old design with some receiving an update.

Expect to see the new bills surface in general circulation within a few weeks.