Specification

This is demo how the drain connected to your ptrap without the glass top & vessel sink. In real
installation, you should put the drain the the surface of the glass top, bottom drain connecting the ptrap.
Step 5: Apply Primer and Cement
Apply PVC primer and PVC cement to the appropriate surfaces and assemble the drain, tying it into the
roughed-in waste pipe. Make sure to hold each connection together for several moments so the chemical
reaction of the primer and cement doesn't force the pieces apart.
here are some videos how to change pop up drain on a similar vanity set, it will help you plumber to
understand how the drain’s tail piece connecting to the ptrap part.
http://www.youtube.com/watch?v=tit9r_-AbdA
http://www.youtube.com/watch?v=NYAwdoe5RTg
http://gmctradesecrets.aol.com/diy/replace-a-pop-up-drain/#!slide=aol_5076199