ITEM NAME:5PCS Ultrasonic Sensor Module HC-SR04 Bracket Holder Raspberry Pi Arduino TO Re Bracket Holder For HC-SR04 Ultrasonic Module Thickness :2.8-3 .1 mm Inner diameter: 16mm Fixing Hole Diameter: 3.8MM Material: Acrylic Application: Fixed ultrasonic sensor modules and other products. Note: This Mounting Bracket only with HC-SR04 ultrasonic ranging module supporting, other ultrasonic modules can not support. Package: 5 x Bracket (color random).Note: This Mounting Bracket only with HC-SR04 ultrasonic ranging module supporting, other ultrasonic modules can not support. Bracket Holder For HC-SR04 Ultrasonic Module. Application: Fixed ultrasonic sensor modules and other products.