Incandescent A-Shape and PS Shape Light Bulb F.A.Q.:
Q: What is an A-Shape light bulb?
A: A-shape refers to the standard light bulbs, traditional light bulbs that you have used in your home for ages. Why are every day, household light bulbs called “A-shape”? I have no idea.
Q: I see you have A15, A19, A21, and A23 A-Shape Light Bulbs. What’s the difference?
A: The number following the “A” in an A-shape light bulb refers to the diameter of the bulb in 1/8” increments. Thus, an A15 light bulb is 15/8” or 1 7/8” diameter. This is true of virtually all light bulb types. They are numbered by a shape designation (like A-shape) followed by the diameter. Why 1/8” increments? I don’t know. I wasn’t consulted.
Q: What are standard light bulbs called, the traditional light bulbs I’ve always used?
A: Traditional, household light bulbs are A19 shape (19/8” or 2 3/8” diameter). These traditional light bulbs may be found at the following link: A19 Shape Light Bulbs
Q: What base type does the standard, household light bulb have?
A: Traditional light bulbs have a “medium base”. The medium base on regular, household light bulbs is also referred to as an E26 base, and E27 base, an Edison base, or a standard base.
Q: I have bulbs that look like regular light bulbs, but the base is smaller?
Q: Has the government banned the use of traditional light bulbs?
A: The 2007 IESA requires the gradual phase-out of standard light bulb. However, more efficient A-Shape bulbs are becoming available that will replace standard light bulbs. These bulbs meet the more stringent lumen per watt guidelines established by Congress. Additionally, the phase-out does not apply to rough-service bulbs. Rough-service bulbs look identical to standard light bulbs, the difference is on the inside. These bulbs have additional supports for the filament that prevent damage to do vibration or rough handling. All of our 130 volt light bulbs are rough-service and will continue to be available.
Q: Can I use 130 volt A-Shape light bulb to replace my traditional light bulbs that are 120 volt.
A: It is perfectly safe to use 130 volt light bulb in place of your regular 120 volt light bulbs. The 130 volt bulbs will be slightly under-powered, thus they will be slightly dimmer. The advantage of 130 volt traditional light bulbs is that they will last 5 times as long (usually rated for 5000 hours).
Q: What is a PS-Shape Light Bulb? It looks a lot like an A-Shape light bulb?
A: You’re right, a PS-Shape light bulb looks very similar to an A-Shape bulb. The main difference is that the PS-Shape Light Bulb has a longer neck, and they are generally wider. Again, the diameter of a PS-Shape light bulb may be determined by dividing the number following the PS by 8 to determine the diameter in inches. PS-Shape light bulbs are generally a higher wattage than A-Shape light bulbs. Many PS-Shape light bulbs are used in industrial applications. Why are they called PS-Shape? Again, I have no idea.