... on their efficiency grade: medium efficiency and high efficiency. They are all two layers structure ... air filter, V-filter and HEPA filter, cabin filter, air cleaner, etc.l Divided into two types:Medium efficiency: TDY-65D,TDY85D,TDY95D High ... saving, environment-friendlyl Usage: mini-pleat air filter, V-filter, HEPA filter, cabin filter, air cleaner, vacuum cleaner filter,etc. air filter material