The Essential Landing Zone Systems Chartbook RC6² allows golfers to find the approximate landing zone when chipping and pitching to the hole with over 1,000 data points. It remove guesswork and frustration from these delicate stroke saving shots around the greens. The ELZS Chartbook contains four in one chartbooks. A chartbook for Slow greens, Fast greens, Super Quick greens, and Ultra Fast greens. So no matter what course you are playing the ELZS Chartbook will approximate landing zones for all green speeds that you may face. These courses include: municipal courses, resort courses, country clubs, to even the courses the pros play on. The ELZS Chartbook is easy and adaptable to use. The chartbook is light weight at only 1 oz, it is also water proof and tear resistant. It is made of recycled plactics and made and printed in the USA.