Traditional testing calls for guesswork and a ruler to measure the distance from mat to chin. Torso-Flex is easier and more accurate. Slide the base under any mat and have the user lie face down. Zero out the tester by resting tester arm on the user's head. Tester mechanically measures trunk lift height as the user performs the test. Molded ABS parts ensure tester longevity. 15”H x 30”L x 9¾”W; 12 lb. Mat not included. Simple assembly. Patented.