At Kaizen we use and highly recommend these for all our vehicle based shooting. 

They are one of the best problem solvers we've purchased in a long while.  No more tapping on the roof or yelling into the drivers window to position the vehicle to take your shot.  If you're shooting with muzzle brakes the front seat pilots don't need to put their fingers in their ears every time they hear a thump on the cabin.  They are so clear that you can whisper a message to each other without fear of scaring away your prey. 

Because they operate in a U.S. UHF frequency you have no fear of anyone eavesdropping on your conversation.

So, if you hunt from a vehicle, a side by side buggy, a four wheeler or motorbikes you are going to love this communication and hearing protection solution.

Keep your hands free and your ears warm while staying in touch with 2, 3, 4 or more members of your group.

Muffs:

• Ultra low-profile, light weight, slim design with rubberized ear cups
• Full Dynamic Range HD speakers amplify safe ambient noise
• Two omnidirectional microphones for clear sound enhancement
• Folds up for easy transport and storage
• NRR 23 protection from noise

Comms:

• Custom designed to integrate onto the Walkers Razor muffs (Muffs sold separately, will not work with Razor Quads)
• 22 Channels (USA UHF frequency - will NOT work in conjunction with any Australian UHF frequency, therefore, will not communicate with your current handheld radio or in-car UHF radio)
• 4 sets can communicate with each other making this the ideal solution for side by sides, quads or utilities where hunters or sports enthusiasts are wanting to communicate with each other
• 2-3 KM range
• Push to Talk / Voice Activated
• Powered by 2 (AAA) batteries included
• Battery Life: 12 hours