(NOTE: 2 sets of this does not support 4 referees. We have 3 referee headset, check ASIN B074W37NQP
We also have 4 referee headset, check ASIN B0768ZTNSG) Descriptions This professional Referee Headset Football Wireless Headsets enable 2 referees to listen and talk at the same time while arbitrating during football games with clear instrction and conversation.

We have pairing video, see below link: https://youtu.be/OcP6PUblH_A

Features
① Two users Real-Time referee headset football headsets communication
② No need hot keys referee headset football headsets, easy to use
③ Memory pairing referee headset football wireless headsets, simple and easy.
④HI-FI sound referee headset football wireless headsets
⑤ High-power football referee communication, which can be used In a noisy environment. Stereo HI-FI headset
⑥ National Level 5 waterproof standard referee headset football headsets

Specification

Referee Headset Football Wireless Headsets Bluetooth version: Bluetooth 5.1
Referee Headset Football Headsets Chip: CSR BC5
Referee Headset Football Wireless Headsets Battery capacity: Upgraded 850mAh, upto 10hours using,
Speaker power: 0.25W
RDS: NO
Referee Headset Football Wireless Headsets Battery type: polymer lithium battery
Referee Headset Football Wireless Headsets Waterproof grade: National Level 5 waterproof standard
Automatic volume adjustment: no
Football Referee Communication Operating voltage: 3.3v-4.2v
Football Referee Communication Talk time: 8h
Football Referee Communication Working temperature: -10-45 degrees Celsius
Charging time: 2.5hour
Standby time: 360hour

Package:

2x V6 Referee Headset Football Wireless Headsets
2x refereee earphones
2x Charging Cables
2x Arm bags

Warranty

1 Year(Within 1 year after you purchase, we supply repair service for free) If you need the accessories for this intercom, you can contact with us.