These are empty semi-transparent TRUEMAN eGo-T&RIVA-T tank cartridges, 

There is no tissue or polyster fiber inside. They are the best match of the TRUEMAN eGo-T atomizers.

Each empty TRUEMAN eGo tank cartridge can carry about 1.2ml e-juice or e-liquid,

which can support 220 puffs. It is enough for a regular user to enjoy half a day!