Stray Kids' Clé 2 : Yellow Wood, released on June 19, 2019, is the group's first special album and fifth extended play. The album features the lead single "Side Effects" (부작용), which delves into the challenges and uncertainties faced during youth, a theme that resonates deeply with STAY, Stray Kids' dedicated fandom. This release also includes three new tracks and all four previously CD-exclusive "Mixtape" songs, offering a comprehensive listening experience that showcases the group's versatility in blending hip-hop, EDM, and K-pop elements. The album achieved significant success, peaking at number two on South Korea's Gaon Album Chart.

Tracklist:

1. Road Not Taken
2. Side Effects
3. TMT
4. Mixtape #1
5. Mixtape #2
6. Mixtape #3
7. Mixtape #4

Inclusions:

• - CD (Random Ver. / Random 1 out of 2)
• - Photobook (Random Ver.)
• * Special Page : Random 1 Out of 9
• - QR Photocards (Random 3 Out of 45)
• - Yellow Wood Card(Pre Order Only / Random 1 out of 9)
• - Photo(Pre Order Only / Random 1 out of 9)