Pre-Pitch Standard Shower Installation Kit 1/8" to 7/8"X36" - Part #: PPK/STD-201, Black Creates the proper code required sub floor pitch. Insures proper pan liner drainage Molded of high impact plastic with re-enforcing design which is light weight and non-rotting. Used on all subfloors wood and concrete Built in slope creates the perfect sub floor slope required without the skill usually necessary to complete a task like this