This is the lid for commonly used travel mug from known manufacturer. There are lots of different lids on Amazon and this one was designed with certain requirements and improvements.
Lid has connection for the stainless steel infuser basket with semitransparent cover cup. Every part is easy to attach/detach and easy to wash.
There are 2 different lids for 2 different mugs and unified connection to use them with the same infuser.