Can GearEye tags be used with metal or liquid?

Radio waves bounce off metal and are absorbed by water at ultra-high frequencies. That makes tracking metal products or those with high water content problematic, but good system design and engineering can overcome this shortcoming. GearEye uses special on-metal tags that can be used on liquid containers or metal items. They are thicker and have the shorter scanning range. These tags are part of some GearEye products