Lockable hole distance measurer with scale (20mm - 200mm) [v1.1]

I always struggled with drilling the holes for wall mounts and pictures. With this handy tool, you can measure the distance between the holes of the thing you want to mount and can lock it in place with the knob. To achieve the perfect pitch, the top of the holes is flat for the placement of small level.

Just place two screws or pencils through the holes and put it on the holes you want to measure. 

There are three versions available: 20cm, 15cm and 10cm. You'll need one knob, one left piece and a right piece with the desired length.

• Recommended layer height: 0.2mm
• Nozzle size: 0.4mm
• Supports: none
• Raft or brim: only when struggling with bed adhesion
• Material: doesn't matter (easily shrinking material can lead to wrong scale)

Edit v1.1: 

Thanks to @tony_259047's great idea, v1.1 now has detachable hole finders you can print to easily locate holes you want to transfer. They can just be printed standing up and should not need supports.