Pre-coated PEI Magnetic Hotbed for 3D Printer

Very sticky and heavy magnetic hotbed

I have a previous one since along time, and due to a horrible filament the coated surface become broken (my fault). Due to this I order a new one. Really do you need to know more??? It's perfect!!

First prints done .
Printer is very good , and quiet enought.
The main problem is belt. Exacly it's tension. There should to be an system that woult let users easly tens the belt.