When should I choose flood or spotlight bulbs, and what's the difference?

<a href="https://www.homedepot.com/b/Lighting-Light-Bulbs-Flood-and-Spot-Light-Bulbs/N-5yc1vZ2fkpcw3?catStyle=ShowProducts?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">Flood light bulbs</a> produce a wide beam, ideal for illuminating large areas like patios or driveways. In contrast, spotlight bulbs focus their beam more narrowly, making them perfect for highlighting artwork or architectural features, giving you options for different needs and purposes. Both can be used indoors or outdoors, depending on the fixture.

Does The Home Depot have different bulb shapes?

Yes! We offer a variety of bulb shapes, including <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/Tubular/Halogen/N-5yc1vZbmbuZ1z0vxiwZ1z21li9?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">tubular</a>, <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/Specialty/Halogen/N-5yc1vZbmbuZ1z0vxiwZ1z1w0qi?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">specialty</a>, and <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/Globe/Halogen/N-5yc1vZbmbuZ1z0vxiwZ1z132or?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">globe</a>.

For bulbs labeled A19, A15, and A21, what does the "A" mean, and how do those numbers relate to the bulb?

The "A" refers to the traditional, pear-shaped bulb, a common style for homes. The number indicates the bulb's diameter at its widest point, in eighths of an inch, so an <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/A19/N-5yc1vZbmbuZ1z0vvrd?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">A19 bulb</a> is 19/8 inches wide, an <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/A21/N-5yc1vZbmbuZ1z0vvpm?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">A21</a> is slightly larger at 21/8 inches, and an <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/A15/N-5yc1vZbmbuZ1z0vvqn?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">A15</a> is smaller at 15/8. Knowing this helps when choosing the right size for your fixtures and the light needed.

What are bi-pin and 4-pin bases, and what are they used for?

<a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/Bi-Pin/N-5yc1vZbmbuZ1z0tnc5?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">Bi-pin bases</a>, including the <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/Miniature-Bi-Pin/N-5yc1vZbmbuZ1z21ms6?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">miniature</a> and <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/Medium-Bi-Pin/N-5yc1vZbmbuZ1z21luf?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">medium bi-pin</a>, have two small pins that push into a socket commonly used for halogen or some LED bulbs in undercabinet lighting or desk lamps. <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/4-Pin/N-5yc1vZbmbuZ1z21lyb?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">4-pin bases</a>, with their four pins, are often found in fluorescent and compact fluorescent (CFL) bulbs; they are designed for fixtures requiring a more secure connection and may need specific ballast compatibility.

What are some popular brands of halogen light bulbs?

Some popular brands known for high-quality halogen light bulbs include <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/INTERLIGHT/Halogen/N-5yc1vZbmbuZztbZ1z0vxiw?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">INTERLIGHT</a>, <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/Feit-Electric/Halogen/N-5yc1vZbmbuZ3zeZ1z0vxiw?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">Feit Electric</a>, and <a href="https://www.homedepot.com/b/Lighting-Light-Bulbs/LUXRITE/Halogen/N-5yc1vZbmbuZsjsZ1z0vxiw?emt=plpfaq_2504_lightbulbs" style="text-decoration: underline;">LUXRITE</a>.