GameCraft Miniatures have released new 15mm terrain pieces.
From their announcement:
We have added two new items that will be of interest to 15mm gamers.
First off is a small defensive fighting position. It’s a great little sandbagged fighting position perfect for a few guys, maybe a mortar or even a very small towed gun.
15mm Small Defensive Fighting Position, Stock #15MSCE003
Next up is another 15mm piece, A large gun emplacement. This piece is perfect for towed artillery, 88mm Flak guns or a few mortars. You could even pull a tank in here for a bit of protection.
Large Gun Emplacement, Stock #15MSCE004