D4 Series Rubberstrap Collection

The D4 Series Danganronpa Rubberstrap Collection (D4「ダンガンロンパ　ラバーストラップコレクション」) is a range of collectible PVC rubber phone straps manufactured by Empty. Each strap is packaged in a blind box and retails for approximately 500-600 Yen. They are approximately 65mm by 45mm in diameter and 6mm thick.

Danganronpa: Trigger Happy Havoc
The Danganronpa: Trigger Happy Havoc set was released in October 2011. It is split over two volumes with 10 straps per volume, totalling 20 straps in the set. 2 straps in each volume are "secret" and unlisted on the packaging.

Danganronpa 2: Goodbye Despair
The Danganronpa 2: Goodbye Despair set was released in March 2013. It is split over two volumes with 10 straps per volume, totalling 20 straps in the set. 1 strap in each volume is "secret" and unlisted on the packaging.

Danganronpa Another Episode: Ultra Despair Girls
The Danganronpa Another Episode: Ultra Despair Girls set was released in February 2015. It is split over two volumes with 8 straps per volume, totalling 16 straps in the set.

Danganronpa 3 - Side: Future
The Danganronpa 3 - Side: Future set was released in November 2016. It is split over two volumes with 8 straps per volume, totalling 16 straps in the set.