Linear-spaced lines; line sizes range from 20/100 to 20/16. Lines are labeled with 20 ft notations only. This chart can either be wall mounted or used in an ESV1200, ESV1500, or a Model A illuminated cabinet. Chart size is 9 in x 14 in (22.9 cm x 35.6 cm)
20 feet, 6 meters testing distance.