Traditional TNT is relatively unstable and can detonate when dropped or when a vehicle carrying it is hit by an IED or a bullet. But the new IMX-101 explosive — while packing the same punch as TNT — is "more thermally stable," says Philip Samuels, a chemical engineer at Picatinny Arsenal's Armament Research, Development and Engineering Center. Researchers spent four years working on the material, which is scheduled for production next year. IMX-101 is more expensive than TNT, with an initial price of about $8 a pound, compared with $6 a pound for the usual stuff. But the Army is happy to pay the price — for soldiers' safety, and because the less volatile explosives can be packed more tightly into storage areas, making them more accessible to soldiers in the field.