Arachnida Ring (3.5e Equipment)
From D&D Wiki
Arachnida rings consist of a pair of matching rings- one of silver and one of gold. A pair of Arachnida rings can only be used by a Spider Rider. The gold ring must be worn by the Rider (it does not count towards her limit of magic items worn unless it grants the Rider), and the silver ring must be worn by the spider (it automatically resizes itself to fit the spider perfectly). The spider can wear up to 8 Arachnida Rings at a time (one on each leg), but can only benefit from two of them at any one time (switching the rings that it benefits from requires a standard action that does not provoke an attack of opportunity). Although the Rider can only actually wear about four of these rings on her hand at a time, she can wear them on a chord round her neck (so that they touch her skin) and still count as wearing them, although the ring must always touch her skin for her (and her spider) to benefit from them. Both must wear the rings to benefit from them. If the Spider Rider becomes an Ex-Spider Rider, she (and her spider) cannot benefit from Arachnida Rings until she recovers her Spider Rider status.