Appears to be 50 steps per revolution. 1-3/4" diameter by only 3/8" thick. Has 3" long 5 wire lead with 6 prong end plug. Has 6/32 threaded shaft 1/2" long. Has two mounting ears, 3-3/16" distance between the two. We are told that this is a great motor for robotics applications but we don't have any additional specs. On the back of the motor is the numbers 6001336 and SI-3420, Japan. Unused. One of our customers provided the following info (Thanks Jim): "I have been working with this motor using a beaglebone black single board computer. The motor is a unipolar stepper motor with 59 ohm windings, which means that it will draw approximately 200 ma of current at 12 volts. The red wire is the common center tap of the two windings. Pulsing the orange, brown, yellow, and black wires in that order will result in clockwise rotation. Pulsing in the opposite order rotates ccw. Operation in this manner results in 100 pulses per revolution (measured). I am using a single pin per phase of a uln2004 darlingon array to drive the motor at 12V. the 200ma draw of the motor is well within the 500ma rating of the chip. This is an excellent single chip driver solution. The motor runs cool when running 120 rpm, which is about its maximum dependable speed in my application. The motor gets slightly warm if a winding is left energized continuously ('hold'). Hopefully this info will help some of your other customers."