This is a Lululemon fake or wannabe, from Tuff Athletics, a light baby blue racerback yoga top with a mesh back pocket.
According to the website, Tuff Athletics was started years ago, pre-Lululemon and its clothing is made in Canada. Most of the Tuff Athletics clothing I have seen was sold in Costco. They also sell similar looking yoga pants and jackets.
Here is a full view of the front of the top. As you can see, there are definite similarities to Lululemon tops.
Here is a close up of the front of the top.
This is a full view of the back of the top. This has a racerback which is often on Lululemon tops.
This is a close up of the bottom of the back of the top. It has a mesh pocket, just like other Lululemon tops.
Here is a view of the bra lining. The lining is the same light blue color, whereas most Lululemon bra linings are beige or nude colored. You can also see the slits for bra cups.
This is a picture of the label of Tuff Athletics. It says that it is Made in Canada.
This top did not have the usual Tuff Athletics flower symbol on it. Their clothing is a lot cheaper than Lululemon but you can definitely see the differences in wear and quality. This is just yet another Lululemon wannabe.