 Item number, SCP-502. Object Class. Safe. Special Containment Procedures. SCP-502 is to be secured in a keypad-locked steel fire cabinet, in the medical suites at... The key code is to be changed on a bi-weekly basis for security reasons. Senior medical staff on site will have knowledge of the key code, as will at least three other on-site personnel of level 3 or higher clearance. Description. SCP-502 was obtained from the Donovan County Coroner's office in Troy, Kansas, in 1991. It was discovered by local coroner during a routine autopsy of a Jared Thomas McIntyre, following his death in a motorcycle collision. SCP-502 was located in the space that should have been occupied by the deceased's heart, and was attached to his pulmonary and circulatory systems. SCP-502 was later retrieved by SCP agents after... Began circulating questions about the box. When unlabeled, SCP-502 has the appearance of an off-white cardboard container with dimensions of 9.75 cm by 9.75 cm by 7.73 cm, with a removable lid measuring 9.95 cm by 9.95 cm by 1.34 cm. The thickness of the cardboard at all locations is exactly 0.10 cm. There are no visible seams on the corners or edges of the box or lid, nor any interior reinforcements. When initially recovered, the item had the word heart, written on it, in cursive handwriting, in what appeared to be blue ink, and had holes in the sides and back that approximated the insertion points of the vena cava, aorta, and pulmonary arteries and veins, as well as internal divisions that resembled the chambers of the heart. When an appropriate organ name is written on the lid of SCP-502, it slowly rearranges itself into a crude approximation of that organ. If a second organ name is written on the lid, the first name written will disappear within 20 minutes, at which time, rearrangement to the new configuration will begin. If all names are erased from the lid, the standard size will be adopted. If SCP-502 is surgically implanted in a human subject, while labeled as an organ, and appropriately attached to the relevant organ systems, it will function in a manner identical to the organ. Testing is determined that SCP-502 will only function under certain circumstances. The subject to receive a replacement organ must be a living human, and must be missing the organ before SCP-502 is introduced to the subject's body. If any of these conditions are not met, the replacement organ will either be rejected, or will not function at all. Following extensive testing, it has been decided by O5 that due to SCP-502's potential life-saving capabilities, it will be kept in storage, and is only to be implanted into a human in case of a life-threatening injury to any director, or in emergency situations with approval of any director to lower-level staff or civilians that must be kept alive temporarily, to assist in SCP-related information gathering or containment. In case of SCP-502 being used to sustain any individual other than a director, the subject is to be terminated as soon as is feasible, and SCP-502 is to be returned to storage. Addendum. For testing procedures, those with level 3 clearance should see documents number 5021 and number 5022. Document number 5021. Test log for initial test phase of SCP-502. 518-91. Lit of box reads heart at beginning of testing. Lung, liver, pancreas, and eye are written on the lid one at a time. On each occasion, the previously written word faded from view over a period of time ranging from 5 minutes 11 seconds to a maximum of 18 minutes 4 seconds. After this, the exterior dimensions and interior design of SCP-502 slowly changed to accommodate the respective organ. When skin is written on the lid, SCP-502 flattened to 1.6 centimeters in thickness and continued to expand in length and width until researchers were forced to erase the word with acetone and allow the box's dimensions to return to default. 523-90. Organ names are written on the lid in a variety of mediums including ink, graphite, oil paint, water-based paint, crayon, blood, and permanent marker. All functioned, although easily erased or damaged mediums often resulted in SCP-502 reverting to its standard size when the word was damaged. 617-90. Organ names are written on the lid in Latin, Greek, Russian, Chinese, Japanese, French, Italian, Esperanto, and SCP-502 showed no reaction except in cases where the organ name was identical in spelling to the English name. Document 5022. Test log for live testing in subjects 5021 through 5026. Subject 5021. Class D subject chosen due to diagnosed renal failure, kidney written on box lid, and time allowed for rearrangement. One of the subjects kidneys is surgically removed. After successful implantation, subject 5021's year analysis shows an improvement in renal function, satisfactory for a healthy individual. SCP-502 is recovered after subjects standard monthly termination. Subject 5022. Class D subject with full renal function, kidney still written on box lid from previous test. One of the subjects kidneys is surgically removed. After successful implantation, subject 501-2's year analysis shows renal function equivalent to that of a healthy individual. SCP-502 is recovered after subjects standard monthly termination. Subject 5023. Class D subject who died in custody due to cardiac failure, heart is written on lid, and time allowed for rearrangement. SCP-502 is successfully implanted and attached to the pulmonary and circulatory systems, but results in no function or reanimation. Subject 5024. Class D subject with no known medical issues, gills written on box lid, and time allowed for rearrangement. Subject's lungs are removed while on life support machinery and replaced with SCP-502, but proper attachment could not be finalized, and subject dies during surgery. Subject 5025. Adult Labrador Retriever suffering from hepatic failure, liver written on box lid, and time allowed for rearrangement. Subject's liver is removed and replaced with SCP-502. However, the SCP is rejected in under 24 hours, and subject dies. Subject 5026. Class D subject with history of mental illness due to a diagnosed brain tumor, brain written on box lid, and time allowed for rearrangement. Subject's brain is removed while on life support machinery and replaced with SCP-502. Upon waking from anesthesia, Subject 5026 data expunged. Two medical staff and three level 2 security personnel are injured, and Subject 5026 is killed by small arms fire during hostilities to prevent further danger to staff. SCP-502 recovered during autopsy, further live testing halted while data expunged, recorded during this incident are being analyzed. Lesson complete. If you missed the previous orientation, go watch SCP-501, Monk's Greed, right now. Or for the complete course, watch this playlist.