High pressure air tanks work great on any paintball marker, but are mostly used on tournament style guns.  Covering your hpa tank with a decorative tank cover is a smart way to protect your tank from dings and scratches.  Tank covers are available for CO2 tanks as well but the best selection is found for hpa tanks.  Paintball gun air tank covers come in a large variety of colors, patterns, cool designs and even custom artwork.  This offers tons of options for customizing your paintball marker/tank with matching accessories.