This is a trigger lock for shot gun Browning 12 calibre. According the EU and local caountry rwquirements the pistols, rifles or shotguns should be kept and transported with such a trigger lock. It's e good idea to keep the guns safe. 

Printed on Bambu Lab X1 Carbon with GD Filament ABS, no support is needed. You could use PLA or PETG as well.