Firing sets and equivalent high-current pulse generators, as follows: a. Explosive detonator firing sets designed to drive multiple controlled detonators specified by Item 6.A.1. above; b. Modular electrical pulse generators (pulsers) having all of the following characteristics: 1. Designed for portable, mobile, or ruggedized-use; 2. Enclosed in a dust-tight enclosure; 3. Capable of delivering their energy in less than 15 μs; 4. Having an output greater than 100 A; 5. Having a 'rise time' of less than 10 μs into loads of less than 40 ohms; 6. No dimension greater than 25.4 cm; 7. Weight less than 25 kg ; and 8. Specified to operate over an extended temperature range of 223 to 373 K (-50 ºC to 100 ºC) or specified as suitable for aerospace applications.