Source: The Book of Many Things

Armor (shield), uncommon (requires attunement)

You can make a ranged weapon attack with this magic shield. It has a normal range of 20 feet and a long range of 60 feet, and it uses your Strength or Dexterity for the attack roll (your choice). If you’re proficient with shields, you are proficient with attacks made using this shield. On a hit, it deals 1d6 slashing damage. If you throw the shield, it reappears in your hand the instant after it hits or misses a target.

A shield is made from wood or metal and is carried in one hand. Wielding a shield increases your Armor Class by 2. You can benefit from only one shield at a time.