SIMPLIFIED DENSITY ALTITUDE - SNIPER DATA BOOK The THUNDER BEAST DATA BOOK will revolutionize how you keep and use a sniper databook or long-range shooting databok. Our Simplified Density Altitude - Sniper Data Book [SDA-SDB] was designed with several goals in mind: (1) Transform data logging from discrete events with an associated set of environmental parameters (altitude, temperature, humidity, etc) to a single lookup using the concept of Density Altitude; (2) Reduce the size, bulk, and weight of the databook compard to conventional databooks that are hundreds of pages by using the MERS (MULTI-ENVIRONMENT REWRITE SYSTEM) permanent/erasable "paper". (3) Provide baseline data good enough to hit man-sized targets at 1000 yards in any conditions, using the supported military cartridges; (4) Make the databook into a "work book" to guide acquisition and verification of ballistic data; (5) Provide "hasty" hold, wind, and lead formulas that are easy to remember and use in the field; More info on the product web page-- http://thunderbeastarms.com/products/databook