For sale, a new NOCH Limestone Rock Wall (Model 58490).

This diorama scenery piece remains factory-sealed.

Measures 32cm x 18cm

More information (from Manufacturer):

The NOCH rock formations are an ideal item to create realistic scenes on your layout. The light weight foam material is easy to use in several ways. The modeller may apply the entire rock face by shaping the edges to blend with the surrounding the scenery. The other method is to cut, saw or break the section into the desired shapes and sizes you wish to create. We recommend using NOCH modelling compound (#60880 or #60890) or hot glue to secure the rock pieces.

Additionally, the rock compound can be used to fill in crevices and to smooth out uneven surfaces.