More info can be found about the collaboration on the Granrodeo website.

Details

Item:  Double-ring pendant; round pendant is engraved with “KISHOW GRANRODEO x PUERTA DEL SOL / LIGHT MY FIRE”; pendant with heart cut-out is ringed with cubic zirconia in black or red. Chain comes in 40 or 50 cm lengths, adjustable
Vendor:  Puerta del Sol (page not active yet)
Price:  27,000 yen
Bonus:  bandanna & special packaging (for orders before 1/7/2020)
Purchase locations:
Online: 2019/12/6 @ 12:00〜2020/1/6 @ 23:59
In-store:  2019/12/6 @12:00〜2020/1/6 @ 20:00