Travel Size Number Search Puzzle Book is the perfect blend of relaxation and brain-training fun. Each hidden number sequence in the grids is designed to test your focus and attention to detail. Convenient travel size 5.5” x 8.5”. - 150 puzzles with solutions. - Each puzzle has 28 6-digit number sequences . - 4,200 number sequences to search for. - One puzzle per page in an easy-to-read layout.