The East Wood Grain Ring slows the loss of weapon durability, making it a prime candidate for use with weapons that have low durability, such as Crystal weapons or Katanas. It's also useful to bring to areas that have enemies that degrade durability, like the Demon Ruins. It does not reduce weapon durability loss from special attacks such as the Drake Sword's two-handed strong attack.
The East Wood Grain Ring allows the player to see the general durability of their current weapon. It is displayed under the stamina bar on the top left hand corner of the screen.