You will need the Adafruit Pi motor hat kit (https://www.adafruit.com/product/2348), a small 5V motor, which you can also get from Adafruit (https://www.adafruit.com/product/711), or many other suppliers, a 4-AA battery case with wire ends and an on/off switch, available from Adafruit (https://www.adafruit.com/product/830) and many other suppliers, 2 gearbox or TT motors, available from Adafruit (https://www.adafruit.com/product/3777) and many other suppliers, and a sticky note (or a piece of paper, scissors, and tape).

Note: If you cannot solder or are uncomfortable soldering, an alternative fully assembled hat can be found on Amazon (https://www.amazon.com/SB-Motorshield-Raspberry-expansion-ultrasonic/dp/B01MQ2MZDV/ref=sr_1_fkmr1_1?s=electronics&ie=UTF8&qid=1534705033&sr=8-1-fkmr1&keywords=raspberry+pi+motor+controller+TB6612). I will note changes in the code where necessary—anytime this chapter references the L293D hat, that is in reference to this hat.