A punch cradle to give even spacing when punching holes with an awl.  My wife uses this one for binding books she uses for junk journaling.  

About the print:

The larger one that fits on the X1/P1/A1 printers is 11" long with 2.5mm holes at ~5mm spacing from edge of one hole to the next.  *Note: should be printed with the aux. fan off to prevent warping of the part on the enclosed printers.

Awl pictured is from this Book binding kit 

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