19 hex sizes included: 3/32-Inch, 7/64, 1/8, 9/64, 5/32, 3/16, 7/32, 1/4, 5/16, 3/8-Inch and 1.5 mm, 2 mm, 2.5 mm, 3 mm, 4 mm, 5 mm, 6 mm, 8 mm, 10 mm

Color coded coating for quick identification of each key size and rust resistance

Heat-treated and tempered for added strength and durability

Ball-End hex keys for working at angles us to 25 degrees

Secure storage with internal locking mechanism to prevent loss of keys

Twist-to-Lock case for hassle-free hex key removal

Cross-compatible, interlocking cases for sleek and convenient storage to stack with other Twist-to-Lock cases