This part is designed for the ZL series of the RailCore II printers.

At only 22 grams of CNC milled aluminum, our new full metal Y plate is the foundation to our new ultralight weight series of Railcore II ZL parts. This Y plate mounts to your X Axis slider and replaces the 3D printed Y plate. With 17 M3 tapped holes, brass inserts are a thing of the past. We understand that ultralight weight and stiffness is of the utmost importance in the drive train of the Railcore series of printers. 

Please note:

This part now comes with the 4 M3 5-6mm screws needed to attach this mount.

Thingiverse link for the Belt Retainer clip, modified BMG mount, and Angled fan mount.

https://www.thingiverse.com/thing:3262662