The original photo and some info is here : Lineaire Actuator aansturen - Forum - Circuits Online
There is a circuit board attached to the stepper motor. What is on that circuit board ? !
It is a "SONCEBOZ 7178 R001".
It is a linear actuator, controlled by a bipolair stepper motor.
There is some information on the internet, but you might have to use Google Translate:
http://www.vandijkenelektronica.nl/main.php?reference=&action=product&categories_id=1&products_id=215&delay=1
Do you live in the Netherlands ?