by Ring
46% Sales Rank in Amazon Devices & Accessories: 50 (was 73 yesterday)
(69)Buy new: $39.99
(Visit the Movers & Shakers in Amazon Devices & Accessories list for authoritative information on this product's current rank.)
source https://www.lifetechnology.com/blogs/life-technology-holistic-health-products-blog/9-ring-contact-sensor-2-pack-alarm-2-white
