SCP-878

Item #: SCP-878

Object Class: Safe

Special Containment Procedures: SCP-878 is to be kept in a padded and soundproofed containment locker in Site-71. The floor of this locker should be made of material that is impervious to water, and the locker itself should be constructed out of materials that will not corrode or rust. Containment is to be monitored via closed circuit television. No personnel are to enter SCP-878’s containment area without wearing Goggles equipped with an infrared camera.

Description: SCP-878 is a hollow, approximately 2.6 meter (9.2 foot) tall, rounded cone-shaped structure consisting of black ceramic and steel, which has a diameter of 3 meters (10 feet). SCP-878's base has been carved out to roughly resemble the shape of an octahedron, though it is imperfectly spherical in shape. SCP-878 is hollow on the inside and resembles a cave or crevice with irregular sides. Its exterior curves back inwards towards its apex. SCP-878 was found submerged in ████'s bay during a Foundation investigation into [REDACTED] cases. The previous owner of SCP-878’s previous owner did not provide any information about its origin or function.

When closed, SCP-878 does not produce any sound despite the fact that it is hollow inside and contains air. However, when open, SCP-878 produces an audible tone that seems to be related to the length of time since the object was closed. Closing the object quickly increases the tone while closing it slowly decreases it almost imperceptibly until stopping completely once the object is fully closed and all air inside has been evacuated by its opening mechanisms; even if open for no more than ten minutes, subjects who have remained within SCP-878 after opening will perceive the tone as constant throughout their entire wait time regardless of how long they wait before opening.

When opened by hand (including via time dilation), subject’s perception of time within SCP-878 slows dramatically to match their perception speed at rest outside of it; subjects will have estimated about 30 minutes had passed in real time for each minute within SCP-878. The amount of time slowing affected subjects experience correlates directly with the number of occupants active inside the object from this point onward until all occupants are deactivated or leave through whatever means available to them; estimated timings for these measures may vary based on individual experience with this anomaly but are consistent throughout all test groups thus far regardless of subjective perception or specific designation of ‘occupant’.

Addendum 878-A: Not all objects with an inside that acts as a soundbox have a tone associated with them. SCP-878 is distinct from this, as tone is not the only anomalous effect of the object. Although these other effects have not been conclusively proven to be related to or caused by SCP-878’s tone, they are worth noting for future potential research.