I just received an order of revetments from Snapdragon Studio the other day so I thought I post a couple of pictures (as there isn't a complete set of pictures on the Snapdragon site).
FFP1 - Straight Plank Revetment (8)
FFP3 - Crew Cutouts (2), Ends (4), Sally Point (1) and Artillery Platform (1)
FFP11 - Straight Trench with Head Logs (6)
The straight sections are roughly 6 inches in length and they are all designed to work with 25/28mm miniatures. The resin castings are pretty clear with very little in the way of bubbles or other blemishes and are of a sufficiently generic design to work for a wide variety of periods. With the first two sets coming in at £11 each and the third at £15, I think these are pretty good value for money. The service from Snapdragon was very good too.