Seal every corner with confidence. The PROVA Inside Preformed Waterproofing Corner delivers fast, reliable waterproofing protection where leaks and mold most often start — corners of showers, tub surrounds, and wet areas. Designed for tile pros who value precision and efficiency, this pre-shaped inside angle corner eliminates cutting, folding, and guesswork for a clean, watertight seal every time.

• Eliminates Guesswork – Ready-to-install 90° inside corner made from PROVA Mat - eliminates trimming, folding and seams.
• Prevents Leaks – Seals critical transitions at shower bases and curbs
• Mold & Mildew Resistant – Inhibits microbial and fungal growth
• Saves Time – Reduce time on every job while ensuring consistent, professional results.
• Smooth Finish for Tile – 25.59 mil (0.65 mm) thick, reduces build-up 
• System-Engineered Compatibility – Works seamlessly with PROVA Mat, Joint Strip, Outside Corners and PROVA underlayment systems.
• Installer-Friendly – Bonds easily with polymer-modified thinset mortar
• Lifetime System Warranty – Backed by PROVA Tile Installation Products Warranty (when installed as part of PROVA Mat Waterproofing System).