D-3340 was a D-Class personnel formerly stationed at SCP Foundation Site-81. In the 1990s, D-3340 was covertly chosen as the subject of the thirteenth test with SCP-3460, alongside D-2321. Their picture was taken and placed in SCP-3460. Two weeks after SCP-3460's needles were manually aligned, D-3340 was scheduled for transfer to Site-88 by Site-81's D-class relocation system, where D-3340 and D-2321 shared a testing schedule.[1]