Heavy steel shield

You strap a heavy steel shield to your forearm and grip it with your hand. A heavy steel shield is so heavy that you can’t use your shield hand for anything else. Whether wooden or steel, a heavy shield offers the same basic protection and attack benefits, though the two versions respond differently to some spells and effects (such as rusting grasp). A druid can use a heavy wooden shield, but not a heavy steel shield.

Shield Bash Attacks: You can bash an opponent with a heavy shield. See “heavy shield” on Table 1–5: Martial Weapons for the damage dealt by a shield bash with a heavy shield. Used this way, a heavy shield is a martial bludgeoning weapon. For the purpose of penalties on attack rolls, treat a heavy shield as a one-handed weapon. If you use your shield as a weapon, you lose its AC bonus until your next turn. An enhancement bonus on a shield does not improve the effectiveness of a shield bash made with it, but the shield can be made into a magic weapon in its own right.