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 Westinghouse?s 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.