A whole 61lbs... Woo.
It has twice the explosive power of TNT, is malleable, and can be molded into small apparently innocuous items. It has virtually no odour which makes it hard to detect by sniffer dogs or sniffer equipment.
Less than half a kilo of Semtex bought down a Boeing &$& over Lockerbie Scotland in December 1988
First, it's 61 pounds. Second, even 6 pounds of that stuff could do some major damage.