Per 
Item #: SCP-4026
Object Class: Safe
Special Containment Procedures:
SCP-4026 is to be kept in a dimly lit standard issue medium security cell with dimensions of 8ft x 8ft x 8ft. Any studies involving SCP-4026 being worn by any subject entering an REM state of being are strictly prohibited between the hours of sunrise and sunset unless specifically allowed by personnel of level 4 security or higher (whatever these hours may be throughout a year) and are to be closely monitored so as to prevent the occurrence of a “Curfew” event caused by disregarding the previous caution. In the occurrence of a “Curfew” event, Team A, consisting of 3 personnel are to remove the subject from their REM state as quickly as possible by any means necessary.
Description:
SCP-4026 is a black colored sleeping mask measuring 30cm in length and 15cm in width. SCP-4026 is composed of an unknown velvety fabric for the eye cover and a black elastic strap connected to each end of the mask. Upon a visual examination of SCP-4026, there appears to be no anomalous properties excepting the unknown fabric.
When worn by a sentient, biological being after sunset (subject must have entered an REM state), they will easily be able to perform lucidity in their dreams, and perform astral projection to such an extent that subjects will be able to vividly describe objects in the area that were unbeknownst to them before they entered an REM state the previous evening. There have even been some accounts in very few tests of the subject wearing SCP-4026 being able to interact with objects in a “dream state” during an astral projection resulting in the same movement in the real world, see incident #4026-a. All activity is stopped if the subject exits REM. But will resume if all previous criteria has been met.
However, if the subject enters an REM state while wearing SCP-4026 after sunrise or before sunset, they will be unable to achieve lucidity or perform astral projection whatsoever. Instead, they will be completely aware of their surroundings, but not be able to perform any physical movements other than breathing. Following this procedure, subjects will begin to see SCP-4026-1 in the corner of the current area they are sleeping in. SCP-4026-1 is a tall, black, shapeless, being; only appearing in the dream of the subject if the previous criteria is met. If not removed from REM, SCP-4026-1 will slowly make its way towards the subject and proceed to sit on the subjects chest and cause them to suffocate extremely quickly. The suffocating process lasts 8-10 seconds. Once SCP-4026-1 has sat on a subject’s chest, it is virtually impossible for them to exit REM see incident #4026-1-a.
All attempts of this procedure have resulted in a 100% mortality rate for all subjects.
Addendum:
Incident 4026-a:
