Capacity (how many lights it can control). The capacity will be measured in watts. Add up the wattage of the bulbs in all the fixtures the switch controls to make sure it falls within the switch rating listed on the package or instructions.
Single-pole or three-way. Buy a ‘single-pole’ switch if one switch controls the lights or a ‘three-way’ if you have two switches controlling the same lights.
Light type. Standard and halogen bulbs require standard incandescent dimmers. A few fluorescent lights can be dimmed with special dimmer switches, but most can’t. Low-voltage lights may also require special dimmers. Plus: These are the 10 things your electrician really wants you to know.
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