A bamboo basket weave. Pretty natural brown of basket weave.

Bamboo Basket Weave Carved® Cherry iPhone 5 Case by kahmier
Check out other Bamboo basket weave Wood Cases at zazzle.com

Shatter-proof, scratch-resistant hardshell with a cushioned rubber insert to provide superior protection for your phone. Fits iPhone 6 Plus Easy access to all ports 

Source: Rusty Sea iPhone Plus 6 Tough Case