The W22s are the in-wall/on-wall version of the M22s. They are designed to fit into rectangular holes in your wall and stick out a couple of inches, just enough for ports and to reduce most of the bad side-effects you get from sticking a speaker in a wall.

http://www.axiomaudio.com/wallspeakers.html

M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8