Two-Way Radios
Retevis RB648 Plus Walkie Talkies, IP67 Waterproof Two Way Radios, High Power Enhanced Coverage, 2000mAh SOS Alarm Rugged, Professional Upgrade Walkie Talkie for Raue Umgebung (2 Pack, Yellow)
Walkie talkies long range; upgraded version of RB648; has a longer range than RB648; can reach 3-5km; long distance signal can reach 350,000 square feet/30 floors; can keep in touch with teammates at any time between convoys or remote mountainous...
https://www.bizrate.co.uk/twowayradios/retevis-rb648-plus-walkie-talkies-oid34871642554.html