Winged Slats have small fringes up and down both sides of the slat.  These small plastic "wings" help to close off the space in the weave of the chain link providing more privacy.

Lock-Top Slats are smooth on both sides and have a routed hole about 6 inches from the top where a strip (included) is slid in horizontally to hold the slats in place.  There is more room left over in the chain link so the privacy factor is lower with this type of chain link slat.

Wind always plays a factor when deciding to place slatting into an existing chain link fence.  Remember that anything that blocks line of sight will also block wind.  Which may in turn cause your fence to sag after time.  We recommend a hole spacing of 8 feet instead of the standard 10 feet when planning to install slats on a tall fence (6' tall or higher).