LEA GRATINGS are for preferential looking test situations with infants
or children and adults with disabilities to determine detection acuity.
Grating levels printed on each handle are: 0.25, 0.5, 1.0, 2.0, 4.0 and
8.0 cpcm (cycles per centimeter of surface). Includes instructions and
storage case. 4 paddles 8" (20 cm) in diameter.