Producing high-strength forged hammers requires expert control over temperature, shaping, and finishing techniques, ensuring ...

Watt, W., Phillips, L. N., and Johnson, W., The Engineer (May 27, 1966). Standage, A. E., and Prescott, R., Nature, 211, 169 (1966).

While it is unknown which of the many available Powergel products was found inside the van, Orica variously described its explosives as “high strength” and “designed to deliver high energy”.