Honda Pioneer SXS700M2P 2019 Owner's Manual page 68

Seat Belts
Rear Seat Belt Holders (SXS700M4P only)
For the rear seat belts, there are seat belt holders to secure the seat
belts when using the cargo bed.
How to secure the seat belt:
Hook the end latch plate of the rear seat belt to the seat belt holder.
seat belt holder
latch plate
58 Instruments & Controls