Honeywell stand-alone carbon monoxide alarm XC100.

The X-Series CO alarms have been optimised for use by professionals dealing with residential CO protection. They have been designed to meet the needs of professional landlords and high demanding private individuals. You can find item with unique part number: XC100
 

High reliability
Low total cost of ownership
Tamper-proof
Easy to install
Complete solution
Designed for residential environments
Easy to operate and use by the end-user