The ELK Products Unfilled "Yellow Jackets" premium quality "B" color-coded connectors are manufactured from the finest materials. They feature insulation piercing internal teeth, soft brass (easy to squeeze) crimp, and a durable protective outer covering. These wire splices have been used in the telecommunications industry for many years. They provide a solid dependable splice in wires ranging from 18 to 30 gauge. The package contains 2 zip lock bags of 250 connectors and a reusable poly storage box.