We Are Bulletproof Pt. 1 is a modified version of the track, “We are B.P.B” that RM and then-trainees Iron and Supreme Boi produced and released before the group’s official debut on October 12, 2010. Even though Iron and Supreme Boi decided not to debut under Big Hit, Supreme Boi still helps produce BTS music under Big Hit. The original version was changed to fit all the 7 members and released on June 8, 2015 as a part of their buildup to their 2nd anniversary.