Ewa-Marine VHF-35 Water & Sand Proof VHF Radio Pouch with Sliding Rail Closure, 15" Tall x 3" Wide x 1.5" Thick.

Protective pouches for VHF radios, on land and at sea
Absolutely water and sand proof! Hearing and speaking is unhindered by the pouch (Ewa-marine measured a quality loss of 5% when using the radio in the pouch). Adjustments can be made from the outside via the finger-glove built into the pouch. If dropped in the water, your VHF-radio will now swim, making it easy to recover.

Many thousands of units are in use with emergency squads, police, Coast Guards etc. Don't be surprised, if the manufacturer of your radio offers you an ewa-marine pouch as part of his accessory list.