50PCS 5.5mm x 2.1mm DC Power Barrel Jack Adapter Breadboard This DC power jack/connector is like another DC power jack/connector we provide, except that it terminates on a breadboard-friendly pin rather than a wide welded terminal. They are also compatible with our DC wall power supply, and have 5.5mm jack, and the center rod diameter is 2.1mm. Features: Achieve the standards of reliable product. Good contact interface and fine electrical property.   Firmly connect and safely connect,not loosen. Buy with satisfaction and use at ease.  Work fluency and durability, which saves your time.  High temperature resistant covers and copper pins, durable and reliable. High matching degree and  perfect matching. Specifications: Type: electronic components, others Color: Black Major Compatibilities: for Diecimila/Duemilanvoe 328, Mega 1280, Mega 2560, 328 Size (L * W * H): 1.45 x 0.90 x 1.00cm / 0.57 x 0.35 * 0.39 inches. Packing weight: 65 g /2.3oz  Package List: 50 * DC Power Barrel Adapters