Trinidad Tackle bait heads are designed for use with Anchovies and other whole baitfish. They are designed to produce a tight, revolving "wounded" fish action that stimulates aggressive feeding fish. Ultra-Violet Blue Violet Jelly Fish effect Changes how anglers use whole bait while trolling the waters of the Pacific and fresh water lakes Ultra-violet light is able to penetrate to depths of 700 feet Works best at daybreak and during low light conditions Un-rigged 2-Pack