3.5" square clear pot
These pots are quite deep (4") and seem much bigger than 3.5". I actually measured them, thinking that I had been sent 4" pots instead. They are UV resistant so do not become brittle after being in the sun, and being clear, they promote good root growth, and let you see what's happening.
3.5" across the top, 2.75" across the bottom and 4" tall.