Lot of 16 books by Mark Greaney.  Including the complete "The Gray Man" Series, books 1-14.l This is a mixture of 4 hardcover and 12 paperbacks. 

1 The Gray Man

2 On Target

3 Ballistic

4 Dead Eye

5 Back Blast 

6 Gunmetal Gray

7 Agent In Place

8 Mission Critical

9  One Minute Out

10 Relentless.  Hardcover

11 Sierra Six.  Hardcover, First Edition

12 Burner.   Hardcover

13 The Chaos Agent

14 Midnight Black.  Hardcover

Armored 

Commander In Chief.  A Jack Ryan Novel by Mark Greaney