wow , that is a great looking diving helmet,
i use to use a miller 400 helmet and let me tell you
you will devolpe really big neck muscles from that .
i also dove a mark v helmet,lots of fun just dont try and walk up side down under the ice, with your feet against the ice .
the exhaust valve got stuck open and before they pulled me out i had water in there up to my nose.... ha ha
that helmet is truly a work of art..