This is a rotary to y axis movement conversion gear set. on the right side of the picture what you see is a adjustable motor holder. you can fix a motor and attached it to the gear. the rotational movement be be convert to linear at the left end of the assembly. the design is fully customization . you can download and customize the design . please remember to like me on my facebook if you like my design https://www.facebook.com/bidtocart