This sensor module is a perfect detector for line follower robot, with 8 IR LED/phototransistor pair mounted in 10mm field. The LED series is arranged to halve the current consumption and the MOSFET allows the LEDs to be turned off for added sensitivity or power savings. Unlike the QTR-8A Reflectance Sensor Array, each sensor provides a separate digital I/O measurable output. Specifications: Dimensions: 75x 13x3 mm ; Working voltage: 3.3-5.0 V ; Supply current: 100 mA ; Output format: Digital I/O compatible ; Output voltage range: with 0 V voltage ; Optimal sensing distance: 3 mm ; Maximum distance detection: 9.5 mm ; Weight: 3.09 g. ;