Anycubic mini - printing bed and easy leveler

I've spent a lot of time in order to properly level my new Anycubic Kossel 3D printer. At the end, I've decided to make a new printing bed out of aluminium (3mm) and print "levelers" with a 3D printer and make the whole leveling process a lot easier, quicker and way more precise.

I've used Stepcraft 840 CNC machine for cutting my first prototype printing bed out of acrylic in order to test the design.

Additional requirements:

6 x M4 screws 25-30mm length (http://www.ebay.co.uk/itm/M4-4