These are miniature DC gearhead motors of the finest quality, made by PortEscap, of the DC Ironless Series. Ironless motors excel at precision applications because of their fast acceleration, smoothness, and other such features. Anyways, these motors for sale are small, very silent, smooth, and precise. Part number M1616M (with the following marking below the part number: 11 207 18 0). They hum along nicely already at 5V, and may also work reliably at higher voltages.
Each motor includes a custom mounting bracket and associated screws to secure the motor to the bracket.
Each motor also includes a small pulley that can be secured onto the shaft with a setscrew.
They are all in excellent physical and operational condition.
Four of the six motors have stock 6" leads terminated in a 0.1" spaced male header for insertion into a breadboard.
$60 for the entire set.