Incandescent A-shape light bulbs come in a variety of sizes and wattages that are perfect for general lighting purposes. To help you find the right bulb for the right application, see Westinghouses full offering of standard A-shape light bulbs including long life, non-stick and commercial service varieties. A-shape light bulbs are available with medium, intermediate and candelabra screw bases making them compatible for use with standard household fixtures everything from table lamps, ceiling fans and appliances to porch lamps and outdoor lanterns.