Arcane Ring (3.5e Equipment)
From D&D Wiki
There was a sorcerer who could not become a wizard. He studied hard but it was in vain. He could not compete with them in arcane knowledge. That's why he created a simple silver ring to make up for that, and so the arcane ring was born giving the user a +5 competence bonus on SRD:Knowledge(arcane) and SRD:Spellcraft skill checks.
Moderate Enchantment;CL 5th; Forge Ring; Cost 1,000 gp; Weight: 0.01 lbs. lb.; Market Price: 2,000 gp