Google Inc’.s Nest Labs is recalling 440,000 smoke detectors, according to a U.S. government notice on Wednesday that provides the first public revelation of how many of the smart home appliances have shipped since sales started in November.

Nest, which Google acquired earlier this year for $3.2 billion, shipped 440,000 of its smoke alarms in the United States between Nov. 15 and April, according to figures contained in a notice by the Consumer Product Safety Commission.

Nest halted sales of the smoke alarms in April after it discovered a defect that could cause users to turn it off unintentionally.

The notice said the recall affected roughly 440,000 units of the $130 Nest Protect sold in the United States at retailers and on the Nest website between Nov. 15 and April 3.

Nest spokesperson Ha Thai said the company does not disclose sales figures and said that the Protect product will be available again “in a few weeks.”

Nest has provided few details about sales of its Protect smoke and carbon monoxide alarm or its 2-year-old smart thermostat, which has earned positive reviews for its sleek look and its ability to help consumers reduce their energy bills.

Tony Fadell, the company’s founder, was quoted in media reports in December saying that “tens of thousands” of the Protect devices had been activated in the first nine days of its availability in the United States, Canada and Britain.

Carl Purvis, a spokesman with the Consumer Product Safety Commission, said the number of units cited in the recall referred to the full production run, including products sold to consumers as well as products shipped to retailers.

Nest said in April that a special feature in its Protect alarm, which allows a user to switch off the device with a wave of the hand, could be inadvertently activated under certain circumstances. The company said it would immediately deactivate the feature on all smoke alarms that are WiFi-connected while it worked on a software update to fix the defect. The company also halted all sales of the smoke alarms to prevent customers from buying a device that would need an immediate patch.

The Consumer Product Safety Commission notice said Nest has received no reports of incidents, injuries or property damage.

Google’s January acquisition of Nest represented the second-largest deal in the Internet search company’s history. The deal positioned Google to play a bigger role in the market for smart home appliances at a time when an increasing array of electronic devices are being designed to connect to the Internet.

(Reporting by Alexei Oreskovic; Editing by Lisa Shumaker)