The Bracelet is the starting weapon of Gyorunton (A character unlocked by either surviving Boss Rush with only 1 weapon equipped or by typing in "secondevolution" within the scrolls of Morbane. Alternatively it is also unlocked through normal play by surviving 30 minutes with either Divano or Gallo. (I recommend Gallo as his +50% max growth is really helpful in maxing our your equipment early).
Unlike the other weapons you do NOT need a passive Item to evolve this weapon. Once you max out the upgrades you can evolve it with a chest and then repeat the process another time to turn the Bi-Bracelet into the Tri-Bracelet.
Divano/Gallo can be unlocked as soon as you get the Scrolls of Morbane WITHOUT affecting achievements (Thanks to NZT21 for confirming this). Divano is unlocked with “quandolodicelui” and Gallo is unlocked with “waitreaction”
If you want to unlock them "legit": my solution for the cheevo below describes the process, it's a rather lengthy one so don't expect to get this achievement until you get past mid-game with this route: