Set with eight rubies and made of silver, the eyes of the spider fitted tightly over the user's head and covered the left eye. When worn, the first ruby was set where the covered eye would be with the rest of the gems rising in a thin line to the crown of the head. The edges of the item were reminiscent of jagged spider legs as if they clung to the wearer.
A protrusion on the inside of the helm would bore through the wearer's eye to keep the device in place when worn.
Whilst worn over the head, the eyes of the spider would affix itself to the wearer's skull by extending a protrusion through the left eye and destroyed it with agonizing pain. It could not be removed until the wearer was dead. Additionally, the eyes of the spider took up the position of both a magic item that covers the head (like a helm or headband) and one that covers the left eye (like an eye of charming). Despite these impediments, the eyes of the spider granted the wearer considerable ocular powers.
- Up to three times a day, the wearer could initiate a gaze attack that ravaged an individual within 30 ft (9.1 m). This effect manifested in much the same way as a ghost's horrifying gaze did.
- The device granted continual all-round vision and true seeing up to 120 ft (36.4 m), making the wearer highly perceptive and nigh impossible to catch off-guard.
- Lastly, the eyes of the spider blocked all mind-affecting effects that attempted to target the wearer.