The Kerdi-Kereck-F Pre-Formed Waterproofing Inside Corners (2-Pack) are pre-formed seamless corners made of Schluter Kerdi for waterproofing inside corners. Made of a polyethylene construction. These inside corners are for use with tile.

Kerdi-Kereck-F waterproofing inside corners are used to waterproof the inside corners of a tiled shower installation before installing tile, and is used with the Kerdi waterproof shower system
For commercial and residential use, only 1 mil thick so there is no build up in the corners and also used for the corners on the Kerdi shower curb
Orange polyethylene construction waterproofs the inside corners of your shower floor, installs before setting your tile makes installation much easier
Easy to install with unmodified thinset (sold separately), use a 1/4 in. x 3/16 in. v-notch trowel to apply thinset, then install Kerdi corners
Kerdi corners are installed before installing the tile