Replacement Kit: GSTB-R STB-BL Safety Sensor Replacement Kit for /Overhead Garage Door Openers, compatible with for /Overhead Garage Door Openers manufactured after 1993. : GSTB-R STB-BL Garage Door Opener Safety Beam Kit with Bracket. The GSTB-R STB-BL safety sensor beam eye emits an beam from inside the garage door, automatically flipping the door open to prevent damage and accidents when an obstruction is detected. Easy Installation: GSTB-R STB-BL Replacement Kit for Garage Door Sensors. you complete installation and use in minutes. Tip: the garage door opener is not powered on before installing the safety backup sensor. Our Mission: Garage door sensor systems are designed to maximum safety during garage door opener operation, protecting children and pets. Color:Black Material:Plastic + Aluminum Package Contents: 1 set * for Genie Garage Door Sensor Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.