If you've ever mounted low voltage boxes, getting them perfect is not the easiest task.  This template has 2 integrated levels to hang the template perfectly square, and the indicators will show you how to mark it properly for the correct size.

Features:

2 bubble levels to level horizontally or vertical

4 centerline divots

Markings for 3 different size boxes

R - Regular single gang boxes

XL - XL single gang boxes (these are the typical Amazon single gang boxes)

DG - Double gang boxes.  Mark to the full width of the box, re-line up to the edge and mark to the DG line.

Cut box outline with a drywall jab saw or an oscillating multitool

You will need (2x) “9.5x40mm Bubble Spirit Level” to super glue to the back side (est. $5 for 8pcs on Amazon)  

This is what I've used: [https://www.amazon.com/dp/B0BVQ7HWVJ?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_3](https://www.amazon.com/dp/B0BVQ7HWVJ?ref_=ppx_hzsearch_conn_dt_b_fed_asin_title_3)

Recommended to print out of PETG, ASA, or another high heat resistant filament.

FOR REFERENCE on my P1S, this took 1hr21min to print (.4mm nozzle, .12mm layers), used 19g of filament and cost $0.30 for my material.

Enjoy!