This is the tried and true Heddon Spook with one tungsten bead in a special chamber to become the one knocker Spook. Familiar "walk the dog" action which may be made easier by the knocker chamber. The knock seems to help draw fish from farther away then the regular spook. Although primarily considered a freshwater lure, I love this lure for early morning flats fishing. There is something about seeing a fish blow up on a topwater lure. All fishing is great fun, but for some reason seeing that charging fish coming at your lure does something for me.
When the time and conditions are right, it is very tough to beat a spook walked across the water. If you haven't used one of these lures, do yourself a favor and put one (or a few) in your tackle bag! I have had good luck on all the colors, but my favorites are bone and ghost.