The MK17 EVO is completely sealed off from the elements, ensuring trouble-free operation no matter how cold or murky the water gets. Its improved internal design allows more airflow from the LP ports which have been reconfigured for better hose routing. Simple and reliable, the air balanced C370 delivers consistent airflow, ease of use and dependability, making it just the ticket for recreational divers in general, and dive travelers in particular. Thanks to its compact size and light weight, this is also a fantastic regulator for our female divers and smaller sized divers. With any of these regulator systems in your dive bag you'll be ready to hit the road.