Here is another robotics kit that you can use to learn how to use sensors and program. The Hobby Hand 2.0 is an open source 3D printed robotic hand with a split frame design. It has 5 servo motors and a frame for additional servo motors for flexion.
The robot hand is 3D printed using PLA or ABS. It is driven by the Arduino MEGA. The complete set weighs about 3 lbs.