This technology is used by the Goa'uld and the Tok'ra. The bombs Goa'uld are powerful explosive devices, from the nucleus of naquadah: overheated by a device at a short charge, the core explodes with immense power. The bombs are of various kinds, from those that can hold in your hand, with limited potential, to those so large and heavy that it must be transported by two Jaffa and can also blow up the 'SGC. Once positioned, the device must be programmed manually for the explosion. It is controlled by the Goa'uld crystals whose internal mechanism is normally protected by force fields.