“The U.S. Consumer Product Safety Commission (CPSC) is warning consumers about the risk of carbon monoxide poisoning from the use of HECOPRO digital display carbon monoxide (CO) detectors.  The CO detectors can fail to alert consumers to the presence of carbon monoxide…Carbon monoxide sensitivity tests performed on the detectors found that they failed to alert when exposed to pre-determined concentrations of carbon monoxide (400 ppm), in violation of relevant safety standards.  If a consumer installs a CO detector that does not alert to the presence of carbon monoxide, and carbon monoxide enters the home, the consumer will not be warned of the presence of this harmful gas, making injury or death very likely…”

CPSC Warns Consumers to Immediately Stop Using HECOPRO Digital Display Carbon Monoxide Detectors Due to Failure to Alert Consumers to Deadly Carbon Monoxide; Sold on Amazon.com | CPSC.gov