Apeace (in Japanese, エーピース; in Korean, 에이피스), formerly known as Double B 21 (더블비21) or Double B, is a boyband from South Korea. The group was the largest K-pop boy band, with 21 members, until 30 June 2014, when it changed to 15 members. As of July 29, 2018, it changed into 10 members.
The group is subdivided into three subunits: Lapis5, Jade5 and Onyx5 (each with 5 members). The members were chosen and produced by Kim Kyungwook, known for working with groups such as H.O.T., Shinhwa and TVXQ.
Until 2015, subgroups performed 6 days a week, 2 times a day at K Theater at Yebisu Garden Place in Ebisu, Shibuya, Tokyo. The group now performs monthly concerts throughout Japan.