Just as you don't know how long you've got left on the planet, but the grim reaper's just counting down the days to the inevitable, so too is there a one way deal going on with this gear - you can see out, but others can't see in. , Size Chart: , Small Size (S) is suitable for Height 90cm , Medium Size (M) is suitable for Height 120cm , Large Size (L) is suitable for Height 140cm