UPDATED 12/2022. While it is true that the seller was great when I needed them, the unit is now a problem.These units sound great and were until the battery that the solar panel charges stopped receiving the charge. You cannot replace these, so the ENTIRE UNIT NEEDS TO BE TOSSED. With the other types, at least you can still use after putting in a Lithium battery. I purchased 3 of these and all three stopped working / charging either before or at the same time I would have needed to replace batteries in nonsolar units - and I have 3 of those types too and they still work.Written in DEC 2021 -- I have three of these motion sensors and they work great. Changing batteries is so 2008! Seller is ON TOP of its service. Responsive, friendly and takes customer service seriously.