Hi-Viz Birdbuster, Magnetic Front Shotgun Sight, Fits Ventilated Ribs 1/4-3/8 Width, Red/Green Finish BB2005 HIVIZ(R) Bird buster Magnetic Shotgun Sight. Includes three sight frames to fit a variety of shotgun rib sizes from 1/4" to 3/8". Includes two Green and two Red replaceable LitePipes in round and triangular shapes.