Per 
Item #: SCP-XXXX
Object Class: Safe
Special Containment Procedures: SCP-XXXX is to be stored in a standard low-security storage locker at Site-████. Due to the nature of SCP-XXXX, no attempts to contact anyone on the other side of SCP-XXXX are to be made as communication with the inhabitants of SCP-XXXX-1 is both redundant and impossible.
SCP-XXXX is not to be considered a safe means of evacuation during a containment breach.
Description: SCP-XXXX is a seamless two-way transdimensional portal approximately two meters by fifty centimeters, encased in a wrought iron frame of French Art Deco design; making the object resemble a nonanomalous wall mirror. At an atomic level, particles cannot freely pass through SCP-XXXX before bouncing off of their SCP-XXXX equivalents; meaning only light and various wavelengths can physically travel across SCP-XXXX.
SCP-XXXX-1 is the collective designation for the reality on the other end of SCP-XXXX, and all entities residing. All instances of SCP-XXXX-1 are anatomically normal humans; albeit with mirrored physical features, reversed handedness, and apparent oppositus.1
Subjects can see clearly through SCP-XXXX into SCP-XXXX-1, but will be unable to physically move through SCP-XXXX on account of subjects meeting the SCP-XXXX-1 equivalent of themselves also attempting to pass through SCP-XXXX at the exact same time. Inhabitants of SCP-XXXX-1 have precisely the same thought processes as inhabitants of this reality and cannot be reasoned or communicated with in any meaningful way
Addendum: All experiments regarding contact between universe prime and SCP-XXXX-1 have been suspended indefinitely (See Experiment Log XXXX).
A handwritten note was found on the back of SCP-XXXX with its discovery; it reads "Qu'importe?"2.
