Quatros are an Iberian weapon usually used in assassination.
Quatros are weapons made from a brass disk with four perpendicular "arms" protruding from it. The "arms" are about eight centimeters (about three inches) long and have sharp point.
Quatros are thrown and one of the points will almost always strike the target.
In The Royal Ranger, Madelyn encounters an Iberian named Benito, working for Jory Ruhl, who tries to scare her into giving up her investigation of misssing children. She tries to follow him, he then throws two quatros at her, she responds by using her sling to kill him.