Adafruit Industries 12VDC 32-Step Stepper Motor

This is a great first stepper motor, good for small projects and experimenting with steppers. This uni-polar motor has a built in mounting plate with two mounting holes. There are only 32 step (11.25 degree) per revolution, and inside is a 1/16 reduction gear set. The shaft is flattened so its easy to attach stuff to it with a set-screw. A perfect first stepper motor and works well with the Motor Shield for Arduino.The gearing has a few side effects which are important to note. First, you can turn the stepper by hand but not as smoothly as an un-geared stepper. It also means you shouldn't use interleaved or micro-stepping to control or it will take forever to turn. Instead use single or double stepping. The torque is fairly high but its slower than un-geared steppers - we maxed out at about 80 RPM when powering with 12VDC and about 50 RPM on 9VDC..