The author remixed this model.
Modified magnet holes to accept 20x7mm encapsulated magnets similar to the original LTT version, these magnets have significantly greater holding power than the disk magnets in the original version.
these are the magnets I used and they fit snugly with no need for glue. https://www.amazon.co.uk/dp/B0B1M1HMGZ
I recomment printing with a minimum 4 side walls and 10 top and bottom layers to add strength, I also printed with adaptive layer hight to smooth out the layer transitions on the arch and added some support to the underside of the arch