I purchased the motion sensors about a year and a half ago. One sensor quite working right but I was happy with the product overall. I thought I’d order a new sensor and went ahead and bought two. I tried to pair them but wouldn’t work. I reached out to customer support and immediately received an answer via email and they informed me that as it turned out I bought the wrong sensors for my receiver. They were extremely helpful. They were very fast in getting back to me and without me even asking, replaced my original bad sensor with no charge or shipping cost. They also directed me to where to find the right receiver to match the two newly purchased ones. These days with all the fast paced environment a customer can sometimes feel forgotten or overlooked. I have to say, that was not my experience with Guardline. They were prompt, patient and went the extra mile to help me. I give them a strong 5 star and will be purchasing all my security equipment from Guardline in the future!