The innovative California-based responsive lighting firm Stack is wowing tech fans with its first shipment of smart bulbs.

Already popular after unveiling new technology created to alert homeowners of disturbances while away called Stack’s Home Awareness, Stack continues to find success with its Stack Classic bulbs and Stack Downlight.

What is especially unique about these smart bulbs is that they fit perfectly in with Stack’s Home Awareness service by essentially watching out for disturbances in an empty household throughout the day. If something untoward occurs, owners are easily and quickly notified via a Stack smartphone alert.

Users don’t have to worry about monthly fees, pricey equipment, or installation hassles since the bulbs are, well, light bulbs that do double duty.

“Our new Home Awareness service provides users with a way of monitoring their home in a simple, non-invasive way, unlike a camera or cumbersome external sensors. The launch of the new Stack Classic allows for full coverage in most homes and provides more granular data with RF sensors embedded in each bulb,” said CEO and founder Neil Joseph.

The brand has also just launched its Home Awareness service, which offers bulbs that mimic an owner’s routine for the appearance of occupancy even when they’re away. Stack bulbs are compatible with Nest and Amazon Alexa.

Stack’s Classic bulb is available for $28, while the Downlight bulb retails for $45.