These light-weight brackets (under 2 g each) are specifically designed for the Pololu 24:1 and 100:1 mini gearmotors. Each bracket features two mounting holes and six mounting slots for #2-size screws, giving you a variety of mounting options. A total of four M2 screws (two for each bracket) are included for securing the motor to the bracket.
The hub pictured works nicely with this bracket.