Hi, I am selling 10 brand new, lastest and most advanced version of Aico Ei650iRF optical smoke alarms (600 series) with 10 year lithium battery - till 2035! This version not only includes RadioLink +, but also includes AudioLink + Data extraction (not all on sale on ebay include that, always check front pic of the box, hence the cheaper price they have) which makes it smartphone friendly and more advanced. If you have any other questions please ask :)
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