An eye cap is a basic plastic device, comparable in size to a contact lens but made from stiffer material, making it less comfortable to wear. Designed with small, sharp protrusions, it blocks the eyelid from reopening once placed over the eye. This mechanism is similar to the spikes used in rental car security that prevent them from being tampered with. Eye caps serve the specific purpose of keeping the eyes of deceased individuals closed, a practice initiated by a mortician.

The eye cap's invention was a practical solution to a common issue faced in mortuary practices. These devices help maintain a peaceful appearance for the deceased by ensuring that their eyes remain shut during viewing and burial. This functionality reflects a unique aspect of the care provided to human cadavers, highlighting the intersection of anatomy, respect, and funerary customs in the treatment of the dead.