The Batman: 10 Best Gadgets
6. Glauca Knife Bat Emblem
When still images of The Batman started to come out, the fans have speculated that the emblem on Batman's chest is made from the gun used to kill his parents and that Bruce modified it as a symbol to keep to heart what he is fighting for.
It was a reasonable hypothesis given the look of the emblem and this Batman's DIY aesthetic quality. Now that the movie is out, the truth is it is a glauca knife that can be easily grabbed from his chest for use in specific situations. Batman has used this glauca knife bat emblem on some occasions during the movie, one of which is breaking into a police investigation location.
While it is not used as such, it can also double as a batarang if the need arise.