If typical numbers prevail, a "proof of design" test is followed by production of 1-8 units, followed by a test of one of the units. The plutonium (2006) that was responsible for the first test was likely 1/4 of the fissile material available, and considering the low-mix design, was poorly crafted and heavy (much too heavy for missile application). The second test (2009) was the approximate yield of the Hiroshima bomb and the design may have been similar. The 2013 test was slightly smaller, and there was no residual nuclear leakage to indicate type or nature of weapon. It is thought the NorKors obtained enough plutonium for 6-8 weapons during the Yongbyon reactor's life. Since the plutonium was theoretically obtained by their now-shuttered Yongbyon 5MW reactor, their attempt to reopen it means they wish to obtain more material for plutonium weapon(s) at the rate of one-two per year. Their enriched uranium program, also at Yongbyon and elsewhere, can produce 2 tons of Low Enriched Uranium (LEU) or, if reconfigured, up to 90 lbs of Highly Enriched Uranium (bomb grade) per year. Depending on configuration and miniaturization (including modern design and use of high-speed switches), this would be enough for 5-10 weapons per year, given a size appropriate for the Taepodong-2 missile. However, in tests, the TD-2 missile has failed to convert to second stage, so technical issues remain. Examination of parts recovered show the manufacture to be crude and basic, with little effort to efficiency. The NK news reports 12-18 deployed TD-2, but evidently they cannot launch them all at once. Command and Control as well as reliability appears to be an issue for this system.