The diameter is from 4 mm to 7 mm(6X15mm motor, 8.5x20mm motor). The overall length is between 10.9 mm and 24.9 mm. The pager motors are widely used for bristlebot motor. The counterweight is rotating the middle length axis. They are available with lead wire, connector and spring terminal. An ideal place to mount a coin type vibration motor is in the plastic shell of your product housings, either directly or wrapped with a rubber holder. Alternatively you can fix it with a solderable mounting bracket PCB through hole wise.