Takenaka Engineering TAKEX Wireless Passive Sensor Transmitter #Serial number is listed on each sensor Model Number: TXF-105WL Battery Housing Unit [Base] [Volumetric Detection Type] Model Number: TXF-105 Sensor Unit ※⚠️#Caution: This wireless passive sensor can only be used with Takenaka wireless transmitters and receivers. ◉Reason for being a jacked item: The spring came off because it wouldn't come off. The batteries were also depleted, so all 4 units had their batteries removed. I believe they are usable and will confirm with a DC11V method. All units have been confirmed to be working. ▶︎⤵︎ ※#Separate Atsumi wireless transmitter "WST100 Transmitter" and passive sensors are available. Contact wireless units (battery-powered) are also available. Detection: Passive Infrared Detection Area: Volumetric Detection Maximum Range: Approx. 12m Weight: Approx. 130g Exterior: Main body cover resin TAKEX Home PDF Wireless Passive Sensor https://www.takex-eng.co.jp/ja/products/category/22/