Manhattan GMAT publishes 9 specialized GMAT Prep Books  this thread is dedicated to the overview of
Manhattan GMAT Books.
Find books by specific area you need to improve  quick reference with recommendations by GMAT Club members:
All currently available Manhattan GMAT Books: Math (Quantitative) GMAT GuidesVerbal GMAT GuidesOther Manhattan GMAT Products
Manhattan GMAT Books 
 Number Properties  Highly Recommended
 Strong section on divisibility rules (how to quickly tell if a number is divisible by 3, 4, 6, 7, etc). This will save time on the test.
 Multiples
 Primes
 factoring
 Odd/even
 Positive/negative
 Powers & roots
 Consecutive numbers
 Remainders
What's Missing:
 No coverage of numbers between 1 and 0 and 0 and 1, and these are some of the trickiest ones
 No strong coverage of absolute values  few of us remember how to do these

 Fractions Decimals and Percents  a little basic
 Fractions
 Decimals
 Percents
 Combination of F, D, and P
 Advanced FDP's

 Equations, Inequalities, and VIC's  Algebra; good for inequalities
 Basic equations
 Equations with Exponents
 Quadratic Equations
 Formulas (includes sequences, patterns, and strange symbols)
 Functions (includes graphs)
 VICs (Variables in Answer Choices)
 Advanced section for equations and formulas

 Word Translations  Highly Recommended; Word Problems
 Algebraic Translations (this is simple word problems)
 Rate and Work problems
 Raios
 Combinations
 Probability
 Statistics
 Overlapping Sets
 Minor Problem Types
 Advanced Work & Rate Problems
 Equations for Exponential Growth

TO BE Continued....
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