Ensure the center of the net meets regulation guidelines with this retractable net height gauge.   Net Checker is a portable and easy device to measure the height of the center of a tennis net accurately and ensuring that it complies with ITF and USTA regulation.  Simply pull the tab and a red line on the tape at 36 in. / 91.4 cm marks the required height that a tennis net should adhere to.  To retract tape, simply press the center of the device. Device is 6 cm in diameter, 1.2 ounces Available in Green, Blue and Pink