Guessing you mean a "clearomiser" (
tank made from plastic or glass) to put on an eGo/evod twist, I would recommend.
small 1.5ml. Aspire K1
medium 2.5ml Eleaf GS air or Aspire mini Nautilus
Just be careful where you buy. There are plenty of shops ready to charge you $20 for a $10 item. There are even some that will put their own logo on a
tank and ask for $30 and then make sure it gets 5 star
reviews all over the internet.