This is the Idler Pulley Plate.  It can be used with V-Slot.  

The idea behind this plate is to give you a mountable yet movable plate for your Smooth Idler Pulley.  This works great as it allows you to easily tension your belt.

There are a lot of possible mounting configurations for this plate.

This design was inspired by Barton Dring of Buildlog.net

6063-T6 Aluminum

Black Anodized Finish

3mm~ (1/8") Thick