What is the difference between TimberStripper and PowerPrep?

PowerPrep is a high strength liquid remover that removes old or weathered timber finishes in poor condition and is designed for exterior use only. PowerPrep will not remove coatings in sound condition. TimberStripper is recommended for their removal. TimberStripper is a paint and timber finish remover (stripper) that removes most water and solvent based finishes and can be used on interior and exterior timber.