Lutron Caseta dimmer switches are typical smart light switches with on/off buttons and dimming controls. However, there’s also a hidden pull-out tab at the bottom for disabling the switch and cutting power when you need to.

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Lutron calls this feature “FASS” on its Caseta light switches, which stands for Front Accessible Service Switch. It’s there for “safe lamp replacement.” In other words, you use it whenever you need to change out the light bulbs in your light fixtures.

This little pull-out tab is located on the bottom of the light switch right below the off button.

Place your fingernail underneath, and you’ll find a little notch that lets you pull the switch out.

This turns the lights off, but it also cuts power to the light switch and light fixture entirely. So as long as that tab is pulled out, you won’t be able to turn the light on at all.

So why is a feature like this necessary? I wouldn’t say that it’s absolutely necessary, but it’s a nice safety feature. When changing a light bulb, it’s always a good idea to cut the power completely. With this pull-out tab, you don’t have to go all the way down to the breaker box. Instead, you can just cut power to the light fixture.

Of course, most people change out bulbs while the power to the fixture is still turned on (which is true even when you turn off the lights at the switch). It doesn’t usually cause any problems, but it’s always better to be safe than sorry should a freak accident occur.